This problem was asked in recent CodeNation Online Test↵
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Given A,B,C — Count the number of valid arrays of size "A" — such that each number of the array is in the range [1,C] — and no subarray of length > B exists in the valid array such that all elements of that subarray are equal ↵
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1<=A<=10^9↵
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1<=B<=50 ↵
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1<=C<=10^5↵
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A = 3 ↵
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B = 1↵
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C = 3 ↵
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O/Putput — 12 ↵
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[121], [123], [131], [132], [213], [212], [231], [232], [312], [313], [321], [323] are all valid arrays. ↵
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Idea = Valid Arrays = Total — Invalid arrays = Counting of Invalid Arrays is easier than valid arrays as far as I can conclude. ↵
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Given A,B,C — Count the number of valid arrays of size "A"
↵
1<=A<=10^9↵
↵
1<=B<=50 ↵
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1<=C<=10^5↵
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A = 3 ↵
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B = 1↵
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C = 3 ↵
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O
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[121], [123], [131], [132], [213], [212], [231], [232], [312], [313], [321], [323] are all valid arrays. ↵
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Idea = Valid Arrays = Total — Invalid arrays = Counting of Invalid Arrays is easier than valid arrays as far as I can conclude. ↵
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