Statistics

Problem Statement for "MajorityElement"

Problem Statement

An array is said to have a majority element x if strictly more than half of its elements are equal to x (see examples for further clarification).

Given a int[] a, return its majority element, or -1 if it does not have one.

Definition

Class:
MajorityElement
Method:
findMajorityElement
Parameters:
int[]
Returns:
int
Method signature:
int findMajorityElement(int[] a)
(be sure your method is public)

Constraints

  • a will contain between 1 and 50 elements, inclusive.
  • Each element of a will be between 0 and 1000, inclusive.

Examples

  1. {3, 9, 3, 3, 7}

    Returns: 3

    Element 3 occurs 3 times, which makes it a majority element of an array with 5 elements.

  2. {0, 1000, 984, 0}

    Returns: -1

    The number of equal elements must be strictly greater than half of array size, so 0 is not a majority element.

  3. {5}

    Returns: 5

  4. {13, 13}

    Returns: 13

    All elements are equal.

  5. {249, 326, 564}

    Returns: -1

    All elements are distinct, so there is no majority element.

  6. {474,474,709,329,709,709,474,700,440,474,474,474,474,474,474,474,474,474,474,474,474,474,474,474,474,474,474,474,474,474,474,474,474,474,474,474,474,474,474,474,474,474,474}

    Returns: 474

  7. {494,494,130,494,266,280,777,599,266,32,778,175,586,175,494,175,586,494,175,175,612,612,586,612,586,586,586,612,586,494,612,175,175,175,612,175,494,612,494,612,612,612,612,612,612}

    Returns: -1

  8. {692,692,681,692,878,140,278,878,278,692,278,692,692,692,692,692,692,692,692,692,692,692}

    Returns: 692

  9. {761,761,831,405,132,936,132,405,405,132,132,158,132,132,405,405,158,405,132,405,132,405,405,405,405,405,405,405}

    Returns: -1

  10. {648,648,956,581,581,581,581}

    Returns: 581

  11. {438,438,190,752,218,625,438,625,438,438,438,438,438}

    Returns: 438

  12. {16,16,16,156,462,16,16,20,84,16,16,156,16,84,16,16,16,16,16,16,16,16,16,16}

    Returns: 16

  13. {635,635,635,411,524,64,635,847,411,236,635,411,236,847,635,236,847,635,236,236,635,635,635,236,236,236,236}

    Returns: -1

  14. {527,527,126,527,47,566,527,67,566,527,527,947,67,947,527,566,947,927,947,947,527,566,566,947,947,947,947}

    Returns: -1

  15. {514,514,952,487,772,380,933,404,288,288,933,380,380,584,288,228,584,380,584,584,584,584,584}

    Returns: -1

  16. {810,810,58,699,527,237,654,527,527,857,397,857,397,397,527,237,857,527,237,527,237,237,237,527,237,237,237,237,237,527,237,237,237,237,237,237,237,237}

    Returns: -1

  17. {801,801,867,243,143,867,143,262,624,143,262,145,624,368,143,368,262,624,867,262,262,262}

    Returns: -1

  18. {457,457,158,457,411,206,408,408,780,958,408,958,408,958}

    Returns: -1

  19. {540,540,687,812,540,397,164,208,397,164,178,812,812,812,812,397,164,685,397,685}

    Returns: -1

  20. {30,30,206,669,235,758,235,919,919,154,235,149,30,147,265,154,646,646,235,147,235,646,147,30,30,147,147,149,149,154,154,30,154}

    Returns: -1

  21. {835,835,514,835,862,793,763,899,514,514,514,793,475,514,450,533,514,514,899,793,672,450,450,763,672,672,793,793,793,337,919,793,450,450,793,793,793,672,919,919,672,919,919}

    Returns: -1

  22. {993,993,57,994,994,994,994,994,994,994}

    Returns: 994

  23. {138,138,546,663,454,615,869,142,142,142,142,142,142,142,142,142,142,142,142,142,142,142,142,142,142,142,142,142,142,142,142,142,142,142,142,142,142,142,142,142,142,142,142,142,142,142,142,142,142,142}

    Returns: 142

  24. {799,799,686,799,799}

    Returns: 799

  25. {26,26,534,26,466,26,466,26,672,26,466,273,26,273,26,26,26,26,26,26,26}

    Returns: 26

  26. {730,730,495,495,495,7,264,495,495,495,7,495,47,7,122,7,122,47,122,7,47,7,7}

    Returns: -1

  27. {176,176,68,25,201,728,283,711,201,201,201,889,889,201,889,201,889,889,889,889,201,201,201,201,201,201,201,201,201,201,201,201,201,201,201,201,201,201,201,201,201,201,201,201,201,201,201,201,201}

    Returns: 201

  28. {422,422,458,188,603,923,917,795,422,38,762,923,923,795,195,195,795,923,923,195,762,762,917,762,762,923,195,923,917,195,917,195,923,917,923,195,195,917,917,195,195,917,917,917,917}

    Returns: -1

  29. {667,667,119,619,619,619,619,619,619,619,619}

    Returns: 619

  30. {392,392,762,762,762,762,762}

    Returns: 762

  31. {606,606,394,64,64,64,64,64,64,64,64,64,64,64,64,64,64,64,64,64,64,64,64,64,64,64,64,64,64,64,64,64,64,64,64,64,64,64,64,64,64,64}

    Returns: 64

  32. {646,646,727,152,760,727,760,463,760,276,760,760,760,760,760,760,760,760,760,760,760,760,760,760,760}

    Returns: 760

  33. {865,865,158,474,140,552,140,140,374,374,374,374,374,374,374,374,374,374,374,374,374,374,374,374,374,374,374,374,374,374,374,374,374,374,374}

    Returns: 374

  34. {212,212,619,231,231,231,231,231,231,231,231,231,231,231,231,231,231,231,231,231,231,231,231,231,231,231}

    Returns: 231

  35. {11,11,727,441,11,656,11,676,11,604,362,11,11,11,11,11,11,11,11,11,11,11,11,11,11,11,11}

    Returns: 11

  36. {698,698,285,610,996,986,986,986,986,986,986,986,986,986,986,986,986,986}

    Returns: 986

  37. {717,717,45,325,228,325,325,24,266,600,860,24,294,24,600,600,325,600,325,600,600,600,600,600,600,600,600,600,600,600,600,600,600,600,600,600,600,600,600,600,600,600,600,600}

    Returns: 600

  38. {316,316,731,731,731}

    Returns: 731

  39. {712,712,707,826,414,501,761,414,323,712,83,83,83,83,83,83,83,83,83,83,83,83,83,83,83,83,83,83,83,83,83,83,83,83,83,83,83,83,83,83,83,83,83,83,83,83,83,83,83,83}

    Returns: 83

  40. {615,615,14,659,659,659,659}

    Returns: 659

  41. {782,782,839,759,536,759,759,759}

    Returns: -1

  42. {605,605,416,153,963,93,593,153,153,93,93,153,153,153,153,153,153,153,153,153,153,153,153,153,153,153,153,153,153,153,153,153,153,153,153,153}

    Returns: 153

  43. {935,935,554,935,220,935,935,789,935,935,935,935,935,935,935,935,935,935,935,935,935,935,935}

    Returns: 935

  44. {202,202,252,252,252,252,252,252,252,252,252,252,252,252,252,252,252,252}

    Returns: 252

  45. {966,966,194,570,255,194,966,194,109,360,109,194,194,194,194,194,966,536,966,238,360,194,194,360,360,360,360,360,360,360,194,194,360,360,194,194,194,194,194,194,194,194,194,194}

    Returns: -1

  46. {85,85,85,85,85,85,979,85,85,85}

    Returns: 85

  47. {501,501,501,763,283,70,803,811,803,763,70,25,803,763,501,70,70,70,70,70,70,70,70,70,70,70,70,70,70,70}

    Returns: 70

  48. {442,442,544,390,390,390,390,390,390,390,390,390,390,390,390,390,390,390,390,390,390,390,390,390,390,390}

    Returns: 390

  49. {38,38,578,492,492,492,492,548,492,492,492,492,492,492}

    Returns: 492

  50. {293,293,734,293,293,293,293,293,293,293}

    Returns: 293

  51. {314,314,852,913,595,875,263,263,263,799,379,913,913,913,379,263,379,379,552,263,552,913,913,263,552,552,263,263,552,263,913,263,913,263,263,913,913,913,913}

    Returns: -1

  52. {587,587,666,743,922,900,922,922,900,71,922,147,147,71,147,922,71,147,587,587,587,587,147,587,587,587,587,587,587,587,587,587,587,587,587,587,587,587,587,587,587,587}

    Returns: 587

  53. {759,759,168,65,713,65,713,484,153,805,759,759,65,759,759,759,759,759,759,759,759,759,759,759,759,759,759}

    Returns: 759

  54. {332,332,637,512,457,838,838,368,457,457,512,838,512,838,838,928,928,838,838,838,928,838,838,838,838,838,838,838,838,838,838,838,838,838}

    Returns: 838

  55. {81,81,729,81,198,968,52,81,293,921,968,968,81,523,968,81,81,81,523,81,81,81,968,968,81,81,81,968,81,81,81}

    Returns: 81

  56. {471,471,360,360}

    Returns: -1

  57. {27,27,814,142,674,665,814,459,815,931,27,992,730,27,458,459,931,931,142,814,897,931,506,931,27,506,459,506,931,506,931,459,931,931,931,459,459,506,459,506,459,931,506,931,931,931}

    Returns: -1

  58. {645,645,777,498,717,717,165}

    Returns: -1

  59. {537,537,242,537,445,537,537,537,537,537,537,537,537,537,537,537,537,537,537,537,537,537,537}

    Returns: 537

  60. {742,742,870,870,870,870,870,870,870,870,870,870,870,870,870,870,870,870,870,870,870,870,870,870,870,870,870,870,870,870,870,870,870,870,870,870,870,870,870,870}

    Returns: 870

  61. {791,791,20,876,573,453}

    Returns: -1

  62. {1000,1000,505,256,1000,536,256,1000,626,9,989,9,820,1000,9,989,9,626,989,1000,626,626,256,989,1000,989,1000,989,989,256,989,256,256,256,989,989,256,989,989}

    Returns: -1

  63. {16,16,596,24,899,596,596,596,596}

    Returns: 596

  64. {872,872,712,750,153,273,697,661,697,159,153,697,697,697,697,697,697,697,697,697,697,697,697,697,697,697,697,697,697,697,697,697}

    Returns: 697

  65. {990,990,152,745,367,509,440,152,395,152,760,760,152,760,152,152,745,760,278,760,278,395,745,760,395}

    Returns: -1

  66. {5 }

    Returns: 5

  67. {13, 13 }

    Returns: 13

  68. {0, 0, 0, 1, 2 }

    Returns: 0

  69. {249, 326, 564 }

    Returns: -1

  70. {1, 2, 3 }

    Returns: -1

  71. {0, 1000, 984, 0 }

    Returns: -1

  72. {0, 0, 0, 0, 0 }

    Returns: 0

  73. {1000, 1000 }

    Returns: 1000

  74. {2, 2, 4, 4 }

    Returns: -1

  75. {1, 2 }

    Returns: -1

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