Given a string S. How many permutations of string s is lexicographically smaller than S . If S = "cda" answer will be 3 . And the strings are {"acd","adc","cad"}.
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Given a string S. How many permutations of string s is lexicographically smaller than S . If S = "cda" answer will be 3 . And the strings are {"acd","adc","cad"}.
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Why shouldn't we count
cad
?Fix the longest common prefix and the next character. The rest are free to take whatever value you want. Possibly use the permutation with repetitions formula