Problem Statement
Johnny wants to become a great programmer, so he practices to improve his programming skills all the time. He thinks he can save a lot of time if he can learn to type faster. It's said that the key to speed typing is keeping the rhythm, which means pressing each key after a constant interval of time. Johnny, like many programmers, loves all kinds of statistics, so he created a program for measuring his typing progress. The program receives a
For this problem you may assume that the average time of one key press will be an integer.
Your task is to calculate which letters take Johnny more than average time to type, so he can practice those letters more. Return a
Definition
- Class:
- SpeedTyper
- Method:
- lettersToPractice
- Parameters:
- String, int[]
- Returns:
- String
- Method signature:
- String lettersToPractice(String letters, int[] times)
- (be sure your method is public)
Notes
- The time needed to press the first key is given by times[0], and the time needed to press the key corresponding to times[i] for all i > 0 is times[i]-times[i-1].
Constraints
- letters will contain only lowercase letters ('a'-'z').
- letters will contain between 1 and 26 characters, inclusive.
- times will contain the same number of elements as the number of characters in letters.
- No letter will occur more than once in letters.
- Each element of times will be between 1 and 100000.
- Elements of times will be in strict ascending order.
- The average time of one key press will be an integer.
Examples
"dcab"
{250, 300, 400, 800}
Returns: "db"
It took Johnny 250 ms to type 'd', 50 ms to type 'c', 100 ms to type 'a' and 400 ms for 'b'. The average time to type a letter is 200 ms so he needs to practice 'd' and 'b' more.
"keyboard"
{100,200,300,500,600,800,900,1200}
Returns: "bad"
It took 200 ms each to type 'b', 'a', 300 ms to type 'd', while it only took 100 ms to type each of the other letters. The average time is 150 ms.
"rewq"
{500, 1000, 1500, 4000}
Returns: "q"
'q' seems to be a difficult letter to type.
"abc"
{2000, 4000, 6000}
Returns: ""
Though the speed is not too impressive, the rhythm is perfect.
"a"
{1}
Returns: ""
"ab"
{3, 4}
Returns: "a"
"ab"
{1, 4}
Returns: "b"
"a"
{1}
Returns: ""
"ab"
{99999, 100000}
Returns: "a"
"ab"
{1, 100000}
Returns: "b"
"wertyuiopasdfghjklzxcvbnm"
{99976, 99977, 99978, 99979, 99980, 99981, 99982, 99983, 99984, 99985, 99986, 99987, 99988, 99989, 99990, 99991, 99992, 99993, 99994, 99995, 99996, 99997, 99998, 99999, 100000}
Returns: "w"
"agofuzmrdsbcwhvtnkyxejlipq"
{4029, 15485, 23926, 25908, 29086, 30463, 41665, 43743, 50585, 57424, 57541, 58711, 58756, 59886, 60434, 61107, 61370, 64452, 65055, 69291, 73115, 74258, 79910, 83166, 95602, 98592}
Returns: "agomdsxelp"
"tfcklxwoqehpjusr"
{6425, 8275, 10108, 11352, 13783, 15706, 16366, 20433, 20983, 36396, 55010, 66614, 81434, 82879, 84596, 93536}
Returns: "tehpjr"
"mpijwxbdhflyecrsqng"
{3060, 13125, 15758, 18784, 24683, 37448, 42985, 48689, 53102, 54709, 56278, 59279, 63210, 77817, 78199, 81995, 82088, 85924, 97546}
Returns: "pwxbdcg"
"bnwmohycxjvqadrekglzpst"
{303, 1577, 1907, 2086, 3751, 11418, 13323, 18187, 18553, 20050, 26519, 31261, 34043, 55093, 58916, 61615, 66072, 67315, 77557, 85111, 94705, 95740, 99636}
Returns: "hcvqdklzp"
"cfwile"
{25532, 62473, 76941, 81649, 83212, 84810}
Returns: "cfw"
"xgtpeqkvdfzwarnbsy"
{2124, 3951, 10203, 12587, 21739, 25064, 25772, 27169, 46286, 53470, 57819, 59340, 63129, 85109, 87867, 91974, 95567, 95688}
Returns: "tedfr"
"fnzlowxkmpghedsyqicbjv"
{6679, 14346, 21773, 23078, 23942, 24942, 32762, 35375, 39300, 44642, 50762, 59706, 59888, 67797, 69798, 75222, 75415, 79297, 79511, 80451, 87334, 93720}
Returns: "fnzxpghdyjv"
"xbtoelvuzapfsgrcyhw"
{11837, 16239, 19999, 24669, 29508, 31246, 38977, 47821, 48977, 57655, 71097, 71465, 76983, 78157, 84351, 85956, 87426, 91046, 93917}
Returns: "xvuapsr"
"mdpqry"
{567, 18610, 26526, 61245, 75904, 82710}
Returns: "dqr"
"dunjh"
{2441, 44806, 80914, 81959, 89830}
Returns: "un"
"kgufozjldbhqrivstexcawmy"
{3437, 18363, 24493, 31294, 31801, 32256, 32302, 33612, 38363, 42419, 44731, 46591, 46778, 46921, 47484, 53805, 54346, 65519, 66516, 73662, 75479, 77652, 88103, 99000}
Returns: "gufdsecmy"
"asqzflwph"
{347, 4982, 36295, 57969, 67748, 71925, 83636, 94233, 97362}
Returns: "qzw"
"ykdfbwnzrtlhmxsgaj"
{2067, 3120, 6377, 9691, 16088, 16188, 20476, 39803, 45286, 55746, 56221, 58748, 72980, 83835, 87657, 87671, 88178, 97884}
Returns: "bzrtmxj"
"tqkwdihcvnsjfmgbyxrzop"
{1091, 3349, 5759, 7252, 14140, 18011, 18381, 25614, 30063, 37561, 37692, 38246, 41786, 47246, 54041, 58962, 63110, 66294, 69958, 75340, 91297, 99792}
Returns: "dcnmgbzop"
"jfh"
{3387, 16106, 54099}
Returns: "h"
"yqdfuiwnmpceshojraxgt"
{128, 3489, 8498, 12100, 25289, 25559, 26661, 36812, 39974, 51582, 59499, 68288, 68700, 75018, 77909, 82482, 84966, 92411, 96625, 98627, 99792}
Returns: "dunpceha"
"ownuvztpqyhf"
{6327, 8571, 25320, 25968, 32186, 54361, 71879, 73709, 75437, 78678, 95207, 96960}
Returns: "nzth"
"aimpsqtlcfudzxywhevkbng"
{1949, 7972, 10945, 13926, 14262, 32050, 35844, 39044, 43298, 45205, 47485, 53370, 60014, 60247, 64356, 67022, 67245, 72451, 73473, 75426, 87655, 90844, 99958}
Returns: "iqdzebg"
"uhqirgvwcynxbsem"
{275, 2529, 7414, 8720, 25074, 30397, 44178, 56693, 70710, 78619, 82110, 86165, 89480, 89783, 95091, 98304}
Returns: "rvwcy"
"lhreouzjwyxqgpnvasmfdb"
{5337, 10135, 19795, 20668, 24207, 28424, 28828, 28897, 29811, 31372, 36756, 39003, 40908, 41416, 48790, 50659, 51688, 59655, 64558, 65620, 68215, 81092}
Returns: "lhruxnsmb"
"enfzpqrjcyiot"
{3185, 14680, 29607, 30472, 33817, 34435, 38502, 45879, 52891, 57271, 64193, 84124, 87867}
Returns: "nfjcio"
"iwgdjankthpycms"
{8417, 10084, 10446, 27473, 37710, 42895, 45563, 47976, 58605, 68887, 82538, 84778, 89796, 91957, 92265}
Returns: "idjthp"
"uceqhjdsxvafmg"
{1228, 5338, 13792, 38486, 51405, 58432, 71851, 73973, 76347, 93441, 95654, 96003, 97232, 99526}
Returns: "eqhdv"
"rdtnjp"
{6778, 9927, 23228, 51716, 68255, 85254}
Returns: "njp"
"rgeczhqidvtwsxman"
{1994, 2648, 8688, 10602, 17352, 17976, 32481, 34730, 35573, 37712, 49886, 53148, 59329, 64014, 66648, 74002, 75361}
Returns: "ezqtsxa"
"hfwvbcpajsixgzdren"
{442, 10527, 13675, 24250, 40137, 50930, 55413, 55574, 55881, 57661, 69796, 71213, 71684, 75309, 76988, 80545, 80831, 82530}
Returns: "fvbci"
"gcnhpokjyfruqlebwi"
{4503, 13953, 20034, 22849, 28197, 40877, 49059, 65093, 79196, 80886, 84656, 86759, 88893, 89567, 95263, 95686, 96048, 98280}
Returns: "cnokjye"
"jrnavz"
{27831, 27835, 34266, 39145, 61884, 69990}
Returns: "jv"
"vyoakpngmefxwhtidqs"
{6096, 12538, 23955, 31074, 34310, 34519, 34780, 35911, 40352, 49198, 54600, 63909, 64378, 67465, 68186, 74708, 80074, 83371, 89965}
Returns: "vyoaefxids"
"ajvkmwyclegsxboqnpdtrzf"
{40, 350, 1889, 2476, 5689, 6412, 17679, 21432, 27039, 34368, 39354, 45775, 46148, 46201, 61418, 68501, 72590, 78335, 79355, 93215, 94151, 94183, 98601}
Returns: "ylegsoqptf"
"gtjfhricaekwbvmydnsopqlux"
{4088, 5813, 8247, 11528, 16955, 23664, 26133, 33311, 35314, 39963, 42351, 42708, 60279, 60799, 72454, 73507, 73569, 74313, 78094, 80427, 81411, 91282, 93388, 93842, 95050}
Returns: "ghrcebmq"
"rzswpvtokfeucjabyngdm"
{1580, 2774, 11440, 16868, 33577, 35109, 37104, 37814, 43370, 58787, 59116, 61285, 63833, 66974, 85857, 88982, 92287, 93990, 95587, 98115, 99939}
Returns: "swpkfa"
"xopkierdmusb"
{43233, 44766, 54490, 64760, 65763, 65912, 68588, 72788, 76695, 78901, 95081, 96792}
Returns: "xpks"
"rwxkyzbqdj"
{12086, 17301, 19308, 20848, 25179, 30172, 32754, 53931, 56262, 81330}
Returns: "rqj"
"yspgonqrjdbec"
{6800, 7134, 16022, 26604, 39849, 43044, 45144, 60108, 60247, 80222, 87970, 91018, 93704}
Returns: "pgordb"
"mdkzgbcsuhjnrxfwpvlteqiya"
{861, 6976, 9321, 14443, 15713, 19144, 19742, 20389, 26970, 31453, 34184, 42169, 48429, 48780, 49625, 51995, 54916, 65868, 76641, 83066, 85375, 85441, 87793, 91286, 91425}
Returns: "dzuhnrvlt"
"j"
{5323}
Returns: ""
"bgkqcavzlmthfueyniwxpsorjd"
{4346, 13930, 16753, 26653, 27195, 31666, 37327, 51840, 52287, 56968, 58920, 59655, 60025, 61451, 66938, 70484, 71529, 71902, 72300, 75992, 81555, 89547, 89726, 92718, 92850, 95238}
Returns: "bgqavzmexps"
"hdbrkipsuoynfav"
{1167, 12777, 25754, 29904, 57470, 67975, 70542, 72420, 75470, 79614, 83609, 91590, 93174, 96521, 97545}
Returns: "dbkin"
"gfcrumnexhqdabytiz"
{8600, 11954, 24354, 25050, 25183, 27847, 36127, 38417, 43830, 44651, 46116, 47189, 54375, 62095, 63739, 72503, 86117, 92484}
Returns: "gcnxabtiz"
"seaoypgrcktwuqxinmlzbhdf"
{58, 17399, 20161, 21065, 21652, 27195, 30719, 34422, 38863, 41653, 53996, 61186, 65147, 67936, 71055, 73930, 74265, 74321, 74674, 78834, 81605, 83320, 89019, 90768}
Returns: "epctwuzd"
"izml"
{20498, 40170, 72983, 93160}
Returns: "m"
"zftorsxvwqaehcbymknjgdupi"
{11559, 16118, 18468, 21272, 31473, 33642, 38193, 43117, 44043, 52966, 53860, 56014, 66356, 66800, 67369, 71243, 76537, 86704, 88296, 89933, 90512, 94079, 97000, 97593, 99125}
Returns: "zfrxvqhmk"
"hkls"
{4265, 29686, 67959, 95904}
Returns: "kls"
"wpnrfyvtsbihkjlgd"
{5374, 6866, 7671, 9705, 17459, 18411, 19795, 20633, 21236, 23855, 24022, 49325, 51393, 61313, 65405, 68925, 96373}
Returns: "fhjd"
"yhwdfgsqiputolkenrz"
{829, 3257, 13230, 14644, 14804, 16707, 23271, 23732, 50361, 51840, 52137, 52659, 60022, 65518, 89763, 90346, 92325, 94387, 97850}
Returns: "wsiolk"
"bdqmxinrlwz"
{3579, 10976, 13255, 15082, 38439, 55742, 61497, 66251, 82095, 89041, 92092}
Returns: "xil"
"fkpducblivseo"
{10830, 15501, 16191, 17123, 27808, 33878, 40643, 45077, 76772, 82311, 85480, 85992, 91260}
Returns: "fui"
"mvjhurlzwnaqyegotkbpi"
{7362, 12289, 13336, 19138, 24752, 29366, 36565, 38499, 38916, 40238, 48783, 50152, 53679, 54308, 58456, 60911, 78813, 94457, 94710, 97421, 99624}
Returns: "mvhulatk"
"gdlcoijnaxwv"
{10023, 12760, 13718, 17377, 39312, 39760, 42015, 42574, 48856, 86941, 89275, 92832}
Returns: "gox"
"bktowgmeuxvzqyr"
{9052, 14161, 28251, 31434, 32449, 34952, 53260, 62346, 70473, 70587, 73830, 88238, 90045, 94227, 96015}
Returns: "btmeuz"
"ofpurgq"
{10352, 12246, 20668, 27292, 38244, 65184, 83013}
Returns: "gq"
"rlabekgjsndquwy"
{5021, 13672, 17498, 28877, 30355, 30733, 34413, 57632, 64936, 64986, 68374, 78646, 80349, 80798, 97635}
Returns: "lbjsqy"
"egotcyfk"
{10201, 24440, 31333, 49766, 58399, 61367, 96331, 97888}
Returns: "gtf"
"mltzqgje"
{1211, 14994, 20518, 20939, 64101, 78450, 97382, 98808}
Returns: "lqgj"
"thiwgmbvlcyseuoafrnpkdx"
{2297, 3445, 9720, 11137, 14054, 15726, 20705, 23639, 32024, 36300, 40553, 43514, 43874, 46525, 48528, 56137, 57593, 67775, 67778, 71891, 81162, 87478, 87952}
Returns: "iblcyarpkd"
"gkjdcwtfrvemspbaxn"
{19, 3531, 19947, 27745, 36025, 38211, 47464, 52680, 57564, 60885, 75478, 78272, 83121, 85484, 94743, 94775, 99252, 99342}
Returns: "jdcteb"
"xyu"
{58310, 70708, 73050}
Returns: "x"
"nt"
{79061, 93200}
Returns: "n"
"kzvhujdctyfbmae"
{12655, 18819, 27204, 48950, 52842, 53283, 54083, 54667, 55221, 55737, 65760, 74770, 86955, 88881, 96105}
Returns: "kvhfbme"
"ehdpomrkfqgwtacnvlusjbx"
{1001, 3621, 11345, 13533, 15735, 16699, 21577, 22378, 31362, 32461, 39265, 44305, 49098, 52852, 58099, 60396, 61961, 68119, 73755, 80283, 89534, 91072, 97635}
Returns: "drfgwtclusjx"
"gudpztrsljamqfniyowecx"
{1773, 1963, 8729, 12092, 14801, 15974, 23264, 31337, 34066, 41536, 44492, 45720, 45915, 58313, 61856, 67929, 70967, 72824, 73746, 86886, 89626, 94886}
Returns: "drsjfiex"
"twhudqrkvyjgfbmpzisnc"
{397, 3660, 21671, 22518, 24499, 25762, 26249, 42113, 42859, 50821, 54483, 54559, 62800, 63329, 68295, 79490, 81008, 81845, 87133, 94596, 98406}
Returns: "hkyfmpsn"
"fstzhkmjyievuboxwpag"
{12404, 13611, 15109, 16519, 16780, 23103, 24846, 30510, 49355, 53342, 74351, 76525, 80987, 81565, 83737, 88887, 93118, 97157, 97239, 99400}
Returns: "fkjyex"
"zbcsxmworekplnvj"
{3572, 17633, 30786, 34048, 37463, 37975, 41468, 47952, 59890, 64245, 64895, 66350, 66624, 68830, 82994, 99664}
Returns: "bcorvj"
"dvmesxiokrqhjzlugtpcbwa"
{14727, 20922, 23779, 26203, 27031, 32385, 34356, 35595, 37573, 40081, 40717, 45705, 55889, 57823, 60643, 61737, 69174, 77379, 84572, 88631, 90601, 90882, 96232}
Returns: "dvxhjgtpa"
"ywzpljtrgxoacbh"
{4702, 7309, 8136, 10776, 15717, 16062, 20304, 20517, 24523, 30480, 33103, 42934, 43635, 46727, 94050}
Returns: "ah"
"emxc"
{10758, 11689, 73995, 98612}
Returns: "x"
"veajizdtpbkhygrs"
{9250, 31990, 33213, 34539, 40832, 41021, 46037, 48534, 64386, 66220, 67262, 76915, 84526, 89585, 90378, 96832}
Returns: "veiphys"
"ltep"
{46322, 58663, 77183, 91076}
Returns: "l"
"rvaokgnemqyjpcu"
{6434, 7018, 7606, 11551, 22082, 39104, 41895, 43676, 49881, 54596, 56508, 68388, 72760, 94403, 96765}
Returns: "kgjc"
"p"
{2684}
Returns: ""
"ifxlnsjw"
{49376, 51886, 55364, 56383, 61332, 61349, 73230, 77136}
Returns: "ij"
"stkuawygrbolq"
{4240, 19657, 23670, 26147, 31838, 35429, 43424, 46919, 61132, 61399, 70470, 72844, 76895}
Returns: "tyro"
"qmsyuxebfvkwpdglcioztjrna"
{1201, 1888, 5330, 5509, 17824, 20506, 24368, 29257, 29924, 39454, 41784, 42745, 49120, 75637, 78286, 80832, 81833, 82689, 88545, 89608, 90912, 91454, 95261, 95586, 99475}
Returns: "ubvpdo"
"vbslorjazqdnyteciuhw"
{355, 4209, 12563, 13190, 14153, 14821, 15930, 18336, 20109, 28260, 34427, 45558, 46645, 55821, 57572, 58277, 58341, 76573, 80266, 92040}
Returns: "sqdntuw"
"ckeiwfbtoxqgdnjphum"
{4465, 6008, 10852, 23435, 26365, 27300, 28988, 30668, 31581, 35628, 39132, 55833, 56070, 74019, 83459, 83646, 86037, 88759, 94164}
Returns: "ignjm"
"rfjenmplbitaso"
{14022, 26204, 26933, 27747, 35141, 46593, 47513, 51045, 51145, 63867, 70940, 79516, 83831, 86772}
Returns: "rfnmita"
"wpihnc"
{4791, 11109, 29557, 67037, 77567, 97182}
Returns: "ihc"
"igfrkobslxyvehtnucdqaz"
{7736, 10488, 11659, 21759, 22737, 27632, 29567, 35625, 46274, 48473, 50392, 52903, 53788, 56826, 67618, 67704, 75726, 76521, 81013, 85837, 88016, 90332}
Returns: "irosltudq"
"vhwlkcdproanqsfeyxgmtib"
{3299, 4584, 9277, 9385, 14496, 15391, 17079, 28039, 34695, 47504, 48074, 53771, 55683, 59936, 66974, 67336, 75346, 81914, 90491, 91909, 96096, 98546, 99705}
Returns: "wkpronfyxg"
"hyiwfkueotdjqgsclabxvrznpm"
{1218, 5489, 8016, 11139, 11359, 11567, 17541, 17789, 18464, 25225, 29112, 29726, 33423, 34198, 45592, 49515, 51402, 58876, 60363, 66385, 83922, 85186, 85541, 86368, 93477, 99866}
Returns: "yutdscaxvpm"
"uvqhjpmratzfobeigsdwynxkc"
{38, 1231, 1636, 1830, 2366, 5424, 18765, 27517, 35782, 37401, 46419, 55922, 61825, 63137, 68538, 68587, 72752, 76793, 77381, 83498, 88518, 90457, 91265, 95923, 96800}
Returns: "mrazfoegswyk"
"mujabilwhgrxqdztvscyop"
{1563, 18383, 22993, 24051, 28297, 34460, 35733, 37224, 38716, 43069, 47376, 47750, 52367, 55022, 61045, 65958, 73941, 77169, 80459, 96129, 96903, 97262}
Returns: "ujiqztvy"
"cqbymudhljkwpzrafitseov"
{2402, 4103, 5535, 7853, 8696, 12745, 14041, 16615, 19910, 21287, 22886, 27682, 36586, 37753, 39499, 44516, 60891, 62349, 64129, 70889, 76006, 83299, 88481}
Returns: "uwpafseov"
"inlpmvgtydburzqxaschjfkew"
{457, 15024, 15927, 18713, 22629, 27255, 31777, 31811, 32858, 43068, 49553, 54007, 55968, 56182, 56310, 58115, 59254, 66989, 73444, 75108, 81478, 82179, 86700, 93759, 97450}
Returns: "nmvgdbuscjke"
"wtjfka"
{7312, 38073, 58818, 76721, 92455, 98268}
Returns: "tjf"
"nkahtvwszmfurcbixdoqyge"
{15955, 21214, 29351, 29987, 30881, 31485, 37634, 38330, 43729, 51328, 66924, 68663, 69491, 71078, 75211, 75280, 84840, 90866, 93874, 94066, 94211, 97732, 98210}
Returns: "nkawzmfxd"
"ajnrcikqvudbsglhexmy"
{17300, 24625, 37636, 39229, 41217, 41453, 45483, 47393, 51115, 56755, 63016, 63336, 65923, 67498, 73599, 78296, 94022, 94985, 99085, 99780}
Returns: "ajnudle"
"yjenmdcwvzpboihsukgfaltq"
{139, 14377, 14788, 21353, 23491, 32157, 32549, 41432, 45643, 48206, 51689, 56810, 57882, 60872, 63150, 74137, 75737, 81169, 81218, 86333, 90617, 93406, 94384, 97944}
Returns: "jndwvbskfa"
"oqmadrt"
{166, 1324, 13491, 76299, 87990, 88967, 89593}
Returns: "a"
"yertzdkbmjsiq"
{2138, 14441, 24712, 25510, 30846, 42203, 46266, 46282, 52087, 64178, 88611, 91209, 97968}
Returns: "erdjs"
"gbordunte"
{19241, 49101, 53334, 59218, 65777, 67607, 78400, 96442, 99972}
Returns: "gbt"
"ygszpmfwct"
{6610, 7241, 13192, 14020, 20936, 21548, 64538, 65772, 75403, 96550}
Returns: "ft"
"dnzfyxr"
{2136, 35998, 52269, 54370, 60038, 74622, 79961}
Returns: "nzx"
"mnkr"
{12163, 36296, 55600, 99840}
Returns: "r"
"cvztguremhsinkxpalfobdw"
{121, 8335, 11507, 11645, 12427, 16704, 18451, 33783, 35737, 42824, 45132, 46521, 51284, 58887, 59836, 65110, 68592, 73523, 75886, 89270, 90891, 92947, 98279}
Returns: "vuehnkplow"
"fcxnerwaotszqyhpmv"
{2932, 7648, 9316, 13027, 16208, 19205, 46120, 54971, 58082, 58761, 59483, 62010, 68222, 68791, 71671, 77935, 91918, 97956}
Returns: "waqpmv"
"iptkwumgonesfbraqyh"
{1012, 17760, 31871, 41057, 43428, 43835, 43927, 45185, 49456, 59211, 59278, 68224, 77245, 80189, 86730, 93106, 94315, 99103, 99408}
Returns: "ptknsfra"
"plkwqoj"
{13780, 18716, 27692, 31209, 45282, 81633, 88683}
Returns: "pqo"
"qwertyuiopasdfghjklzxcvbnm"
{75, 176, 277, 378, 479, 580, 681, 782, 883, 984, 1085, 1186, 1287, 1388, 1489, 1590, 1691, 1792, 1893, 1994, 2095, 2196, 2297, 2398, 2499, 2600}
Returns: "wertyuiopasdfghjklzxcvbnm"
"dcab"
{250, 300, 400, 800 }
Returns: "db"
"keyboard"
{100, 200, 300, 500, 600, 800, 900, 1200 }
Returns: "bad"
"dcab"
{200, 300, 450, 800 }
Returns: "b"
"a"
{100 }
Returns: ""
"abcd"
{50, 100, 150, 200 }
Returns: ""
"abc"
{2000, 4000, 6000 }
Returns: ""
"abc"
{1000, 1100, 1200 }
Returns: "a"
"adfg"
{1000, 1001, 5001, 5004 }
Returns: "f"