Statistics

Problem Statement for "FoxSequence"

Problem Statement

Fox Ciel likes sequences. One day, she invented a new type of sequence and named it the fox sequence. A sequence seq containing N elements is called a fox sequence if and only if there exist four integers a, b, c and d such that 0 < a < b <= c < d < N-1 and the following five conditions are met:
  • seq[0], seq[1], ... , seq[a] forms an arithmetic progression with a positive common difference. An arithmetic progression is a sequence where the difference between successive elements is equal. The difference between successive elements is called the common difference. Note that 0 is neither positive nor negative.
  • seq[a], seq[a+1], ... , seq[b] forms an arithmetic progression with a negative common difference.
  • seq[b], seq[b+1], ... , seq[c] are all equal.
  • seq[c], seq[c+1], ... , seq[d] forms an arithmetic progression with a positive common difference.
  • seq[d], seq[d+1], ... , seq[N-1] forms an arithmetic progression with a negative common difference.

In the following image, the top 3 sequences are fox sequences, while the bottom 3 sequences are not:



You are given a sequence seq. Return "YES" if it is a fox sequence, or "NO" if it is not (all quotes for clarity).

Definition

Class:
FoxSequence
Method:
isValid
Parameters:
int[]
Returns:
String
Method signature:
String isValid(int[] seq)
(be sure your method is public)

Constraints

  • seq will contain between 1 and 50 elements, inclusive.
  • Each element of seq will be between 1 and 2,000, inclusive.

Examples

  1. {1,3,5,7,5,3,1,1,1,3,5,7,5,3,1}

    Returns: "YES"

    This is the top-left sequence of the image shown in the statement. The next five examples are also from that image.

  2. {1,2,3,4,5,4,3,2,2,2,3,4,5,6,4}

    Returns: "YES"

  3. {3,6,9,1,9,5,1}

    Returns: "YES"

  4. {1,2,3,2,1,2,3,2,1,2,3,2,1}

    Returns: "NO"

  5. {1,3,4,3,1,1,1,1,3,4,3,1}

    Returns: "NO"

  6. {6,1,6}

    Returns: "NO"

  7. {1}

    Returns: "NO"

    N=1

  8. {20,19}

    Returns: "NO"

    N=2

  9. {5,5}

    Returns: "NO"

    N=2

  10. {7,8}

    Returns: "NO"

    N=2

  11. {1,2,1,2,1}

    Returns: "YES"

    smallest fox

  12. {3,5,8}

    Returns: "NO"

    N=3

  13. {12,18,12}

    Returns: "NO"

    N=3

  14. {30,99,30,99}

    Returns: "NO"

    N=4

  15. {55,99,65,65}

    Returns: "NO"

    N=4

  16. {34,45,56,9}

    Returns: "NO"

    N=4

  17. {3,2000,1,1998,2}

    Returns: "YES"

    N=5, fox

  18. {1,2000,3,4,3}

    Returns: "YES"

  19. {500,501,1,3,1}

    Returns: "YES"

  20. {123,456,345,789,678}

    Returns: "YES"

  21. {862,1923,37,1845,943}

    Returns: "YES"

  22. {5,901,899,902,901}

    Returns: "YES"

  23. {2000,2000,2000,2000,2000}

    Returns: "NO"

    N=5, non-fox

  24. {1,1,1,1,1}

    Returns: "NO"

  25. {1,1,3,3,5}

    Returns: "NO"

  26. {300,400,500,600,700}

    Returns: "NO"

  27. {12,45,46,45,49}

    Returns: "NO"

  28. {812,1423,1422,1734,1982}

    Returns: "NO"

  29. {1,2,1,2,3}

    Returns: "NO"

  30. {1,2,3,2,1}

    Returns: "NO"

  31. {1,2,3,2,3}

    Returns: "NO"

  32. {5,4,3,2,1}

    Returns: "NO"

  33. {9,9,6,9,6}

    Returns: "NO"

  34. {6,9,9,9,6}

    Returns: "NO"

  35. {6,9,9,12,6}

    Returns: "NO"

  36. {6,9,6,6,9}

    Returns: "NO"

  37. {6,9,6,9,9}

    Returns: "NO"

  38. {1293,1413,1533,1334,1485,1310}

    Returns: "YES"

    N>=6, fox (random)

  39. {1507,1561,1394,1422,1299,1176}

    Returns: "YES"

  40. {830,1022,1001,1001,1064,843}

    Returns: "YES"

  41. {1194,1350,1175,1000,1047,1020}

    Returns: "YES"

  42. {624,859,593,605,617,520}

    Returns: "YES"

  43. {135,333,531,729,927,1125,1323,1521,1719,1917,1767,1779,1791,1803,1815,1827,1839,1662,1485,1308,1131}

    Returns: "YES"

  44. {160,278,396,514,632,750,596,442,288,134,134,134,134,134,408,682,956,912,868,824,780}

    Returns: "YES"

  45. {565,816,1067,1318,1569,1820,1747,1674,1601,1528,1455,1382,1309,1236,1163,1090,1017,944,944,966,988,1010,1032,1054,1076,1098,1120,1142,1164,1186,1208,1230,1252,1274,1296,1318,1340,1362,1384,1406,1428,1450,1322,1194}

    Returns: "YES"

  46. {848,866,884,902,836,770,704,638,572,572,572,572,572,572,572,572,572,572,572,572,605,638,671,704,737,770,803,836,869,902,935,968,1001,1034,1067,1100,1133,1166,1199,1180,1161,1142,1123,1104}

    Returns: "YES"

  47. {898,1040,1182,1324,1466,1411,1356,1301,1246,1191,1136,1136,1136,1136,1136,1136,1136,1136,1136,1136,1136,1136,1360,1354,1348,1342,1336,1330,1324,1318,1312,1306,1300,1294}

    Returns: "YES"

  48. {455,500,545,590,635,680,725,770,815,860,905,950,995,1040,1085,959,833,707,581,581,581,581,581,581,581,581,581,581,581,581,581,581,581,739,897,1055,1213,1371,1529,1687,1845,1715,1585,1455,1325,1195,1065,935}

    Returns: "YES"

  49. {935,1085,1235,1385,1098,811,811,811,846,881,916,951,986,1021,1056,1091,1126,1161,1196,1231,1266,1301,1336,1371,1308,1245,1182,1119,1056,993,930,867,804,741,678,615}

    Returns: "YES"

  50. {637,674,711,748,785,822,859,896,933,970,1007,1044,1081,1118,1155,1192,1229,1266,1303,1340,1377,1287,1197,1107,1107,1229,1127}

    Returns: "YES"

  51. {1395,1516,1637,1758,1573,1388,1203,1018,833,648,463,278,93,93,93,203,313,423,533,643,753,863,973,1083,1193,1303,1413,1523,1486,1449}

    Returns: "YES"

  52. {802,816,830,844,858,872,886,900,914,928,942,956,935,914,893,872,872,872,872,872,872,872,872,872,872,872,872,872,872,872,872,872,872,872,872,872,872,872,872,872,1056,1240,1424,1608,1590,1572}

    Returns: "YES"

  53. {372,451,530,609,688,767,846,925,1004,985,966,947,928,909,890,871,852,833,814,795,776,776,852,928,1004,1080,1156,1232,1308,1384,1460,1536,1373,1210,1047,884,721}

    Returns: "YES"

  54. {1343,1353,1363,1373,1383,1393,1403,1413,1423,1433,1443,1453,1463,1473,1483,1493,1503,1430,1357,1284,1211,1138,1065,992,919,919,919,1107,1295,1483,1671,1859,1842,1825,1808,1791,1774,1757,1740,1723,1706,1689}

    Returns: "YES"

  55. {980,1174,1368,1562,1756,1950,1706,1462,1218,1218,1218,1218,1218,1218,1218,1218,1218,1218,1218,1218,1218,1218,1218,1218,1218,1218,1218,1218,1218,1218,1218,1395,1340,1285,1230,1175,1120,1065,1010}

    Returns: "YES"

  56. {1340,1439,1538,1394,1394,1394,1394,1394,1394,1394,1394,1394,1394,1394,1394,1394,1405,1416,1427,1438,1449,1460,1321,1182,1043,904,765,626}

    Returns: "YES"

  57. {168,255,342,429,516,603,690,777,864,951,1038,1125,1212,1299,1044,789,534,534,534,534,534,534,534,735,936,1137,1338,1539,1740,1587,1434,1281,1128,975,822,669,516}

    Returns: "YES"

  58. {1000,1050,1100,1150,1200,1250,1300,1350,1400,1450,1500,1450,1400,1350,1300,1250,1200,1150,1100,1050,1000,1000,1000,1000,1000,1000,1000,1000,1000,1000,1000,1050,1100,1150,1200,1250,1300,1350,1400,1450,1500,1450,1400,1350,1300,1250,1200,1150,1100,1050}

    Returns: "YES"

    N=50, fox (beautiful fox sequence)

  59. {1,2000,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,2000,1}

    Returns: "YES"

    N=50, fox (maybe edge cases)

  60. {1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,46,47,46}

    Returns: "YES"

  61. {1,2000,1999,1998,1997,1996,1995,1994,1993,1992,1991,1990,1989,1988,1987,1986,1985,1984,1983,1982,1981,1980,1979,1978,1977,1976,1975,1974,1973,1972,1971,1970,1969,1968,1967,1966,1965,1964,1963,1962,1961,1960,1959,1958,1957,1956,1955,1954,1955,1954}

    Returns: "YES"

  62. {1,2,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,46}

    Returns: "YES"

  63. {1999,2000,1999,2000,1999,1998,1997,1996,1995,1994,1993,1992,1991,1990,1989,1988,1987,1986,1985,1984,1983,1982,1981,1980,1979,1978,1977,1976,1975,1974,1973,1972,1971,1970,1969,1968,1967,1966,1965,1964,1963,1962,1961,1960,1959,1958,1957,1956,1955,1954}

    Returns: "YES"

  64. {2000,1967,1934,1901,1868,1835,1802,1769,1736,1703,1670,1637,1604,1571,1538,1505,1472,1439,1406,1373,1340,1307,1274,1241,1208,1175,1142,1109,1076,1043,1010,977,944,911,878,845,812,779,746,713,680,647,614,581,548,515,482,449,416,383}

    Returns: "NO"

    Straight Chain(non-fox)

  65. {616,616,616,616,616,616,616,616,616,616,616,616,616,616,616,616,616,616,616,616,616,616,616,616,616,616,616,616,616,616,616,616,616,616,616,616,616,616,616,616,616,616,616,616,616,616,616,616,616,616}

    Returns: "NO"

  66. {3,37,71,105,139,173,207,241,275,309,343,377,411,445,479,513,547,581,615,649,683,717,751,785,819,853,887,921,955,989,1023,1057,1091,1125,1159,1193,1227,1261,1295,1329,1363,1397,1431,1465,1499,1533,1567,1601,1635,1669}

    Returns: "NO"

  67. {460,491,522,553,584,615,646,677,708,739,770,801,832,863,894,925,956,987,1018,1049,1080,1111,1142,1173,1204,1235,1266,1297,1328,1301,1274,1247,1220,1193,1166,1139,1112,1085,1058,1031,1004,977,950,923,896,869,842,815,788,761}

    Returns: "NO"

    2-Chain

  68. {1888,1889,1890,1853,1816,1779,1742,1705,1668,1631,1594,1557,1520,1483,1446,1409,1372,1335,1298,1261,1224,1187,1150,1113,1076,1039,1002,965,928,891,854,817,780,743,706,669,632,595,558,521,484,447,410,373,336,299,262,225,188,151}

    Returns: "NO"

  69. {1474,1477,1480,1483,1486,1489,1492,1495,1498,1501,1504,1507,1510,1513,1516,1519,1522,1525,1528,1531,1534,1537,1540,1543,1546,1549,1552,1555,1558,1561,1564,1567,1570,1573,1576,1579,1582,1585,1588,1591,1594,1597,1600,1603,1606,1609,1612,1615,1618,563}

    Returns: "NO"

  70. {398,429,460,491,522,553,584,615,646,677,708,739,770,801,832,863,894,925,956,987,1018,1049,1080,1111,1142,1173,1204,1235,1266,1239,1212,1185,1158,1131,1104,1077,1050,1023,1023,1023,1023,1023,1023,1023,1023,1023,1023,1023,1023,1023}

    Returns: "NO"

    3-Chain

  71. {264,295,326,357,388,419,450,481,512,543,574,605,636,667,698,729,760,791,822,795,768,741,714,687,660,633,606,579,552,525,525,525,525,525,525,525,525,525,525,525,525,525,568,611,654,697,740,783,826,869}

    Returns: "NO"

    4-Chain

  72. {923,969,1015,1061,1107,1153,1199,1245,1291,1337,1288,1239,1190,1141,1092,1043,994,945,896,847,847,847,847,900,953,1006,1059,1112,1165,1218,1271,1324,1377,1430,1483,1536,1589,1541,1493,1445,1397,1349,1301,1253,1205,1157,1109,1061,1013,12}

    Returns: "NO"

    +1 Noize at tail

  73. {923,969,1015,1061,1107,1153,1199,1245,1291,1337,1288,1239,1190,1141,1092,1043,994,945,896,847,847,847,847,900,953,1006,1059,1112,1165,1218,1271,1324,1377,1430,1483,1536,1589,1541,1493,1445,1397,1349,1301,1253,1205,1157,1109,1061,1013,431}

    Returns: "NO"

  74. {923,969,1015,1061,1107,1153,1199,1245,1291,1337,1288,1239,1190,1141,1092,1043,994,945,896,847,847,847,847,900,953,1006,1059,1112,1165,1218,1271,1324,1377,1430,1483,1536,1589,1541,1493,1445,1397,1349,1301,1253,1205,1157,1109,1061,1013,192}

    Returns: "NO"

  75. {923,969,1015,1061,1107,1153,1199,1245,1291,1337,1288,1239,1190,1141,1092,1043,994,945,896,847,847,847,847,900,953,1006,1059,1112,1165,1218,1271,1324,1377,1430,1483,1536,1589,1541,1493,1445,1397,1349,1301,1253,1205,1157,1109,1061,1013,1013}

    Returns: "NO"

  76. {500,969,1015,1061,1107,1153,1199,1245,1291,1337,1288,1239,1190,1141,1092,1043,994,945,896,847,847,847,847,900,953,1006,1059,1112,1165,1218,1271,1324,1377,1430,1483,1536,1589,1541,1493,1445,1397,1349,1301,1253,1205,1157,1109,1061,1013,965}

    Returns: "NO"

    +1 Noize at head

  77. {1280,969,1015,1061,1107,1153,1199,1245,1291,1337,1288,1239,1190,1141,1092,1043,994,945,896,847,847,847,847,900,953,1006,1059,1112,1165,1218,1271,1324,1377,1430,1483,1536,1589,1541,1493,1445,1397,1349,1301,1253,1205,1157,1109,1061,1013,965}

    Returns: "NO"

  78. {1066,969,1015,1061,1107,1153,1199,1245,1291,1337,1288,1239,1190,1141,1092,1043,994,945,896,847,847,847,847,900,953,1006,1059,1112,1165,1218,1271,1324,1377,1430,1483,1536,1589,1541,1493,1445,1397,1349,1301,1253,1205,1157,1109,1061,1013,965}

    Returns: "NO"

  79. {969,969,1015,1061,1107,1153,1199,1245,1291,1337,1288,1239,1190,1141,1092,1043,994,945,896,847,847,847,847,900,953,1006,1059,1112,1165,1218,1271,1324,1377,1430,1483,1536,1589,1541,1493,1445,1397,1349,1301,1253,1205,1157,1109,1061,1013,965}

    Returns: "NO"

  80. {923,969,1015,1061,1594,1153,1199,1245,1291,1337,1288,1239,1190,1141,1092,1043,994,945,896,847,847,847,847,900,953,1006,1059,1112,1165,1218,1271,1324,1377,1430,1483,1536,1589,1541,1493,1445,1397,1349,1301,1253,1205,1157,1109,1061,1013,965}

    Returns: "NO"

    +1 Noize at random position

  81. {923,969,1015,1061,1107,1153,1199,1245,1291,1337,1288,1239,1190,1141,1092,1043,994,945,896,847,847,847,847,900,953,1006,1059,1112,1165,1218,1271,1324,1377,1430,1483,1412,1589,1541,1493,1445,1397,1349,1301,1253,1205,1157,1109,1061,1013,965}

    Returns: "NO"

  82. {923,969,1015,1061,1107,1153,1199,1245,1291,1337,1288,1239,599,1141,1092,1043,994,945,896,847,847,847,847,900,953,1006,1059,1112,1165,1218,1271,1324,1377,1430,1483,1536,1589,1541,1493,1445,1397,1349,1301,1253,1205,1157,1109,1061,1013,965}

    Returns: "NO"

  83. {923,969,1015,1061,1107,1153,1199,1245,1291,1337,1288,1239,1190,1141,1092,1043,994,483,896,847,847,847,847,900,953,1006,1059,1112,1165,1218,1271,1324,1377,1430,1483,1536,1589,1541,1493,1445,1397,1349,1301,1253,1205,1157,1109,1061,1013,965}

    Returns: "NO"

  84. {1933,1807,1681,1555,1429,1303,1177,1051,925,771,617,463,309,155,155,155,155,280,405,530,655,780,905,1030,1155,1280,1405,1530,1655,1780,1905,1667,1429,1191,953,715}

    Returns: "NO"

    5-separator

  85. {1331,1447,1563,1679,1795,1795,1795,1795,1795,1795,1795,1795,1795,1795,1795,1795,1795,1795,1795,1795,1795,1795,1795,1795,1795,1795,1795,1795,1795,1795,1795,1795,1795,1753,1711,1669,1627,1585,1543,1501,1459,1417,1375}

    Returns: "NO"

  86. {1699,1657,1657,1657,1657,1657,1657,1657,1657,1657,1657,1657,1657,1657,1657,1657,1657,1657,1657,1657,1657,1657,1657,1657,1657,1657,1657,1657,1657,1657}

    Returns: "NO"

  87. {846,1329,1037,745,453,161,170,179,188,197,206,206,206,206,206,206,206,206,206,206,206,206,206,206,206,206,206,206,206,206}

    Returns: "NO"

  88. {1815,1815,1815,1815,1815,1815,1815,1815,1815,1815,1815,1694,1573,1452,1331,1210,1089,968,847,726,605,484,363,363,363,363,363,363,363,363,308,253,198,143,88,181,274,367,460,553,646,739,832,925,1018,1111,1204,1297,1390,1483}

    Returns: "NO"

  89. {1736,1610,1484,1484,1484,1484,1484,1484,1484,1484,1484,1484,1484,1484,1484,1484,1484,1484,1484,1484,1484,1484,1484,1484,1484,1484,1484,1484,1484,1484,1484,1484,1484,1484,1487,1490,1493,1496,1499,1502,1505,1037,569,569,569,569,569,569,569,569}

    Returns: "NO"

  90. {1014,1014,1014,1014,1014,1014,1014,1014,1014,1014,1014,1014,1014,1014,1014,1014,1014,1014,1014,1014,1014,1014,1014,1014,1014,1014,1014,1014,1014,1014,1014}

    Returns: "NO"

    4-Separator

  91. {627,627,627,627,627,627,627,627,627,627,627,627,627,627,627,627,627,627,627,627,627,627,627,735,843,951,530,109,109,109,109,109,109,109,109}

    Returns: "NO"

  92. {1437,968,499,30,123,216,309,379,449,519,589,659,729,799,869,939,1009,1079,1149,1219,1289,1359,1429,1499,1569,1639,1639,1639,1639,1639,1639,1639,1639,1639,1639,1639,1639,1639,1639,1639,1639,1639,1639}

    Returns: "NO"

  93. {33,91,149,207,265,323,381,381,381,381,381,381,381,381,381,381,381,381,381,381,381,381,381,381,381,381,381,381,381,360,339,318,297,276,255,234,213,192,171,171,171}

    Returns: "NO"

  94. {157,157,157,157,157,157,157,157,157,157,157,157,157,157,157,157,157,157,157,157,157,157,157,157,157,157,157,157,157,427,697,967,967,967,967,967,967,967,967,967,967,967,967,967,967,967,967,967,967,967}

    Returns: "NO"

  95. {1846,1678,1510,1342,1265,1188,1111,1111,1111,1111,1111,1111,1111,1111,1111,1111,1111,1111,1111,1111,1111,1111,1111,1111,1111,1111,1111,1111,1111,1111,1111,1111,1111,1111,1111,1111,1111,1111,1111,1111,1111,1111,1111,1111,1111,1111,1111,1111,1111,1111}

    Returns: "NO"

  96. {1082,1108,1134,1160,1186,1229,1272,1315,1358,1401,1444,1487,1530,1573,1616,1389,1162,935,708,481,613,745,877,1009,1141,1273,1273,1273,1273,1273,1273,1273,1273,1273,1273,1273,1273,1273,1415,1557,1699,1841,1983}

    Returns: "NO"

    6-Separator

  97. {65,65,65,65,65,65,97,129,161,193,225,257,289,289,289,197,105,105,105,105,105,105,105,105,105,105,105,105,105,105,105}

    Returns: "NO"

  98. {65,65,65,65,65,65,97,129,161,193,225,257,289,289,289,197,105,105,105,105,105,105,105,105,105,105,105,105,105,105,105}

    Returns: "NO"

  99. {1183,1270,1357,1444,1531,1618,1705,1792,1514,1826,1650,1474,1298,1122,946,992,1038,1084,1130,1176,1222,1268,1268,1268,1268,1268,1268,1268,1268,1268,1268,1268}

    Returns: "NO"

  100. {1478,1105,732,732,732,732,732,732,732,732,732,732,732,732,732,732,732,732,732,732,508,284,60,60,60,60,60,60,60,60,60,60,60,60,60,60}

    Returns: "NO"

  101. {1056,1179,1302,1425,1430,1435,1440,1445,1450,1455,1460,1465,1470,1475,1480,1485,1490,1495,1500,1505,1510,1515,1520,1525,1530,1388,1246,1246,1246,1246,1246,1246,1303,1360,1417,1474,1531,1588,1645,1645,1645,1645,1645,1645,1645,1645,1645,1645,1645,1645}

    Returns: "NO"

  102. {2000,1,2000,1,2000,1,2000,1,2000,1,2000,1,2000,1,2000,1,2000,1,2000,1,2000,1,2000,1,2000,1,2000,1,2000,1,2000,1,2000,1,2000,1,2000,1,2000,1,2000,1,2000,1,2000,1,2000,1,2000,1}

    Returns: "NO"

    ZigZag

  103. {3,1999,2,2000,1,2000,1,2000,2,2000,1,2000,2,1999,2,1998,3,1999,2,2000,3,1998,3,1998,3,1998,3,2000,2,1999,2,2000,1,1998,1,1998,2,1999,2,1998,2,1999,3,2000,2,1998,3,1999,2,1999}

    Returns: "NO"

    ZigZag part 2

  104. {833,736,1952,396,782,794,1671}

    Returns: "NO"

    Completely Random (Small)

  105. {500,1345,1122,707,1355}

    Returns: "NO"

  106. {1611,1127,870,1407,1483,1411,770}

    Returns: "NO"

  107. {55,1356,1779,562,1411,1464,1530,541,938,1286,1775,1539,1741,16,876,651,625,1301,1346,431,1094,334,85,1382,1168,251,1078,1952,1325,737,463,17,896,651,476,1628,955,1059,1306,775,76,8,873,318,759,352,1548,141}

    Returns: "NO"

    Completely Random (Large)

  108. {1742,56,1325,289,1796,650,1987,275,2,1743,705,1269,1287,948,887,1643,1542,1269,1836,1129,1331,1281,1962,1413,1486,1937,811,1726,728,1927,1473,1724,1692,140,426,1845,130,1234,727,28,1272,307,1872,452,1120,1194}

    Returns: "NO"

  109. {745,852,69,1525,794,1231,1560,1142,540,390,1535,259,1393,239,1052,137,93,604,37,1299,928,762,1758,365,1342,757,621,1513,438,275,1506,1717,349,511,848,840,192,1270,1646,815,1570,1545,363,1215,1033}

    Returns: "NO"

  110. {1000,1050,1100,1150,1200,1250,1300,1350,1400,1451,1500,1450,1400,1350,1300,1250,1200,1150,1100,1050,1000,1000,1000,1000,1000,1000,1000,1000,1000,1000,1000,1050,1100,1150,1200,1250,1300,1350,1400,1450,1500,1450,1400,1350,1300,1250,1200,1150,1100,1050}

    Returns: "NO"

    +alpha

  111. {1000,1050,1100,1150,1200,1250,1300,1350,1400,1450,1500,1451,1400,1350,1300,1250,1200,1150,1100,1050,1000,1000,1000,1000,1000,1000,1000,1000,1000,1000,1000,1050,1100,1150,1200,1250,1300,1350,1400,1450,1500,1450,1400,1350,1300,1250,1200,1150,1100,1050}

    Returns: "NO"

  112. {1000,1050,1100,1150,1200,1250,1300,1350,1400,1450,1500,1450,1400,1350,1300,1250,1200,1150,1100,1050,1001,1000,1000,1000,1000,1000,1000,1000,1000,1000,1000,1050,1100,1150,1200,1250,1300,1350,1400,1450,1500,1450,1400,1350,1300,1250,1200,1150,1100,1050}

    Returns: "NO"

  113. {1000,1050,1100,1150,1200,1250,1300,1350,1400,1450,1500,1450,1400,1350,1300,1250,1200,1150,1100,1050,1000,1000,1000,1000,1000,1000,1000,1000,1000,1000,1000,1051,1100,1150,1200,1250,1300,1350,1400,1450,1500,1450,1400,1350,1300,1250,1200,1150,1100,1050}

    Returns: "NO"

  114. {1000,1050,1100,1150,1200,1250,1300,1350,1400,1450,1500,1450,1400,1350,1300,1250,1200,1150,1100,1050,1000,1000,1000,1000,1000,1000,1000,1000,1000,1000,1000,1050,1100,1150,1200,1250,1300,1350,1400,1451,1500,1450,1400,1350,1300,1250,1200,1150,1100,1050}

    Returns: "NO"

  115. {1000,1050,1100,1150,1200,1250,1300,1350,1400,1450,1500,1450,1400,1350,1300,1250,1200,1150,1100,1050,1000,1000,1000,1000,1000,1000,1000,1000,1000,1000,1000,1050,1100,1150,1200,1250,1300,1350,1400,1450,1500,1451,1400,1350,1300,1250,1200,1150,1100,1050}

    Returns: "NO"

  116. {1, 3, 5, 7, 5, 3, 1, 1, 1, 3, 5, 7, 5, 3, 1 }

    Returns: "YES"

  117. {6, 1, 6 }

    Returns: "NO"

  118. {100, 100, 100, 100, 100, 100, 100, 100, 100, 100, 99, 98, 97, 96, 95, 94, 93, 92, 91, 90, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 99, 98, 97, 96, 95, 94, 93, 92, 91, 90, 89, 88, 87, 86, 85, 84, 83, 82, 81 }

    Returns: "NO"

  119. {1, 3, 4, 3, 1, 1, 1, 1, 3, 4, 3, 1 }

    Returns: "NO"

  120. {1 }

    Returns: "NO"

  121. {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50 }

    Returns: "NO"

  122. {2, 2, 1, 2, 1 }

    Returns: "NO"

  123. {10, 10, 9, 9, 10, 11, 10 }

    Returns: "NO"

  124. {1, 2, 3, 4, 5, 6, 7, 7, 7, 7, 7, 7, 8, 9, 10, 11, 8, 5, 2 }

    Returns: "NO"

  125. {5, 4, 3, 4, 5, 6, 5, 4, 3, 4, 5, 6 }

    Returns: "NO"

  126. {1, 2 }

    Returns: "NO"

  127. {1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1 }

    Returns: "NO"

  128. {1, 2, 1, 2, 1 }

    Returns: "YES"

  129. {1, 2, 1, 2, 1, 1 }

    Returns: "NO"

  130. {9, 6, 3, 1, 9, 5, 1 }

    Returns: "NO"

  131. {1, 4, 5, 7, 5, 3, 1, 1, 1, 3, 5, 7, 5, 3, 1 }

    Returns: "NO"

  132. {1999, 2000, 1999, 1999, 1999, 1999, 1999, 1999, 1999, 1999, 1999, 1999, 1999, 1999, 1999, 1999, 1999, 1999, 1999, 1999, 1999, 1999, 1999, 1999, 1999, 1999, 1999, 1999, 1999, 1999, 1999, 1999, 1999, 1999, 1999, 1999, 1999, 1999, 1999, 1999, 1999, 1999, 1999, 2000, 1999 }

    Returns: "YES"

  133. {2, 1, 2, 1, 2 }

    Returns: "NO"

  134. {1, 1, 1, 1, 1, 1, 1 }

    Returns: "NO"

  135. {3, 2, 1, 2, 3, 2, 1 }

    Returns: "NO"

  136. {3, 6, 4, 4, 4, 8 }

    Returns: "NO"

  137. {1, 2, 4, 3, 4, 3 }

    Returns: "NO"

  138. {1184, 361, 235, 1314, 386 }

    Returns: "NO"

  139. {50 }

    Returns: "NO"

  140. {1, 2, 3, 4, 5, 6 }

    Returns: "NO"

  141. {1, 2, 2, 3, 2 }

    Returns: "NO"

  142. {3, 1, 1, 1, 1, 2, 1 }

    Returns: "NO"

  143. {10, 11, 12, 13, 11, 9, 9, 12, 15, 11, 8 }

    Returns: "NO"

  144. {1, 3, 5, 7, 4 }

    Returns: "NO"

  145. {2, 1, 1, 2, 3, 2, 1 }

    Returns: "NO"

  146. {3, 6, 9, 1, 9, 5, 1 }

    Returns: "YES"

  147. {5 }

    Returns: "NO"

  148. {2, 2, 1, 1, 2, 1 }

    Returns: "NO"

  149. {3, 3, 2, 3, 2 }

    Returns: "NO"

  150. {1, 3, 5, 4, 1, 3, 5, 3, 1 }

    Returns: "NO"

  151. {2, 3, 2, 3, 2, 3 }

    Returns: "NO"

  152. {1, 2, 1, 2 }

    Returns: "NO"

  153. {3 }

    Returns: "NO"

  154. {5, 5, 5, 5, 5, 5, 5, 5 }

    Returns: "NO"

  155. {3, 2, 1, 2, 2, 1, 2 }

    Returns: "NO"

  156. {6, 5, 3, 1, 7, 1 }

    Returns: "NO"

  157. {3, 2, 3, 2, 5 }

    Returns: "NO"

  158. {1, 2, 1, 5, 3 }

    Returns: "YES"

  159. {3, 3, 2, 2, 4, 2 }

    Returns: "NO"

  160. {1, 2, 3, 3, 3 }

    Returns: "NO"

  161. {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1 }

    Returns: "YES"

  162. {2, 3, 4, 5, 6, 5, 4, 3, 4, 5, 6, 5, 4, 1 }

    Returns: "NO"

  163. {2, 2, 1, 3, 1 }

    Returns: "NO"

  164. {1, 2, 3, 4, 5, 4, 3, 3, 3, 2, 1 }

    Returns: "NO"

  165. {1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1 }

    Returns: "NO"

  166. {1, 20, 40, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 20, 40, 1 }

    Returns: "NO"

  167. {1, 2, 3, 4 }

    Returns: "NO"

  168. {3, 2, 1, 2, 1 }

    Returns: "NO"

  169. {2, 2, 2, 2, 2 }

    Returns: "NO"

  170. {1, 2, 3, 5, 8, 7 }

    Returns: "NO"

  171. {1094, 1891, 302, 1256, 1851, 182 }

    Returns: "NO"

  172. {5, 6, 5, 3, 1, 2, 1 }

    Returns: "NO"

  173. {10 }

    Returns: "NO"

  174. {1, 2, 3, 2, 1 }

    Returns: "NO"

  175. {3, 1, 3, 1 }

    Returns: "NO"

  176. {4, 5, 4, 4, 3, 1 }

    Returns: "NO"

  177. {7, 5, 4, 3, 3, 4, 3 }

    Returns: "NO"

  178. {1, 2, 3, 3, 4, 5 }

    Returns: "NO"

  179. {7, 7, 7, 5, 3, 1, 1, 1, 3, 5, 7, 5, 3, 1 }

    Returns: "NO"

  180. {1, 2, 3, 4, 5, 4, 3, 2, 1 }

    Returns: "NO"

  181. {1, 5, 1, 1, 2, 3, 4, 5, 4, 3, 2, 1, 43 }

    Returns: "NO"

  182. {1, 2, 2, 1, 2 }

    Returns: "NO"

  183. {1, 2, 3, 2, 1, 1, 1, 2 }

    Returns: "NO"

  184. {10, 10, 9, 9, 10, 9 }

    Returns: "NO"

  185. {2 }

    Returns: "NO"

  186. {3, 2, 1, 1, 2, 3, 2, 1 }

    Returns: "NO"

  187. {3, 6, 9, 1, 1, 9 }

    Returns: "NO"

  188. {1, 2, 3, 4, 3, 2, 2, 2, 3, 4, 5, 6, 6, 6, 6, 6 }

    Returns: "NO"

  189. {1, 3, 5, 7, 5, 3, 3, 3, 5, 7 }

    Returns: "NO"

  190. {1000, 1100, 1000, 1100, 1200, 1300, 1400 }

    Returns: "NO"

  191. {5, 4, 2, 4, 2 }

    Returns: "NO"

  192. {1, 2, 1, 3 }

    Returns: "NO"

  193. {4 }

    Returns: "NO"

  194. {1, 10, 9, 9, 8, 3 }

    Returns: "NO"

  195. {10, 9, 8, 7, 6, 7, 8, 9, 9, 9, 9, 8, 7, 6, 5, 6, 7, 8, 9, 10 }

    Returns: "NO"

  196. {1, 2, 3, 3, 2, 1, 2, 1 }

    Returns: "NO"

  197. {1, 2, 10, 1, 2, 1 }

    Returns: "NO"

  198. {1, 2, 1, 1, 1 }

    Returns: "NO"

  199. {1, 3, 8, 10, 3, 4, 3 }

    Returns: "NO"

  200. {1, 2, 1, 2, 2 }

    Returns: "NO"

  201. {1, 2, 3, 2, 1, 2, 3, 2, 1, 2 }

    Returns: "NO"

  202. {2, 2, 1 }

    Returns: "NO"

  203. {3, 3, 3, 2, 1, 1, 2, 3, 2, 1 }

    Returns: "NO"

  204. {7, 7, 7, 7, 5, 3, 1, 1, 1, 3, 5, 7, 5, 3, 1 }

    Returns: "NO"

  205. {3, 6, 8, 11, 15, 16 }

    Returns: "NO"

  206. {2, 2, 1, 3, 2 }

    Returns: "NO"

  207. {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13 }

    Returns: "NO"

  208. {10, 20, 10, 20, 10 }

    Returns: "YES"

  209. {1, 2, 3 }

    Returns: "NO"

  210. {1, 2, 2, 3 }

    Returns: "NO"

  211. {1, 2, 2, 3, 1 }

    Returns: "NO"

  212. {1, 3, 3, 5, 1 }

    Returns: "NO"

  213. {1, 7, 6, 1, 2, 1 }

    Returns: "NO"

  214. {1, 2, 3, 5, 7, 7, 8, 7 }

    Returns: "NO"

  215. {2, 1, 2, 1, 2, 1 }

    Returns: "NO"

  216. {1, 3, 5, 7, 4, 6, 4, 2 }

    Returns: "YES"

  217. {1, 1 }

    Returns: "NO"

  218. {1, 3, 6, 4, 2, 2, 8, 12, 7, 2 }

    Returns: "NO"

  219. {2, 2, 1, 1, 2, 3, 2, 1 }

    Returns: "NO"

  220. {1, 3, 5, 6, 7, 7, 7, 8, 3 }

    Returns: "NO"

  221. {5, 4, 4, 5, 4 }

    Returns: "NO"

  222. {1, 2, 3, 4, 5, 6, 7, 8, 9, 8, 7, 6, 5, 4, 3, 2, 1, 2, 3, 4, 5, 6, 7, 8, 9, 8, 7, 6, 5, 4, 3, 2, 1 }

    Returns: "YES"

  223. {1, 3, 5, 7, 5, 3, 1, 1, 1, 3, 5, 7 }

    Returns: "NO"

  224. {4, 3, 1, 2, 1 }

    Returns: "NO"

  225. {1, 3, 5, 7, 4, 1, 1, 1, 1, 3, 5, 7, 5, 3, 1 }

    Returns: "YES"

  226. {1, 2, 3, 5, 7, 7, 7, 8, 9, 11, 13 }

    Returns: "NO"

  227. {1, 2, 3, 4, 5, 6, 7, 8 }

    Returns: "NO"

  228. {6, 1, 6, 1 }

    Returns: "NO"

  229. {3, 3, 2, 1, 1, 2, 3, 2, 1 }

    Returns: "NO"

  230. {1, 2, 3, 4, 5, 4, 3, 2, 1, 1, 1, 1, 1, 2, 3, 4, 5 }

    Returns: "NO"

  231. {1, 3, 5, 7, 5, 3, 1, 1, 1, 3, 5, 7, 5, 3, 1, 3, 5 }

    Returns: "NO"

  232. {1, 3, 5, 7, 5, 3, 1, 1, 1, 3, 5, 7, 7 }

    Returns: "NO"

  233. {1, 2, 3, 2, 1, 1, 2, 3, 3 }

    Returns: "NO"

  234. {1, 2, 3, 4, 5, 6, 7, 8, 9, 8, 7, 6, 5, 4, 3, 2, 1, 2, 3, 4, 5, 6, 7, 8, 9, 8, 7, 6, 5, 4, 3, 2, 1, 1 }

    Returns: "NO"

  235. {1, 2, 5, 2, 1, 2, 5, 2, 1 }

    Returns: "NO"

  236. {1, 2, 4, 3, 2, 3, 2 }

    Returns: "NO"

  237. {5, 4, 2, 2, 3, 2 }

    Returns: "NO"

  238. {1, 2, 3, 3, 3, 4, 5, 5 }

    Returns: "NO"

  239. {1, 2, 4, 5, 4, 3, 3, 3, 4, 5, 4, 3 }

    Returns: "NO"

  240. {1, 5, 1, 5, 1 }

    Returns: "YES"

  241. {5, 4, 3, 3, 4, 3 }

    Returns: "NO"

  242. {6, 4, 1, 1, 2, 1 }

    Returns: "NO"

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