#K58127. Lexicographic Rank of Permutations
Lexicographic Rank of Permutations
Lexicographic Rank of Permutations
Given a string S, compute its lexicographic rank among all its permutations sorted in alphabetical order. The rank of the smallest permutation is defined as 1. The computation uses the formula:
\[ \text{Rank}(S) = 1 + \sum_{i=0}^{n-1} \left( \text{Count}(i) \times \frac{n!}{(n-i)!} \right) \]
where n is the length of the string, and \( \text{Count}(i) \) is the number of characters to the right of the i-th character that are smaller than S[i]. The factorial function is defined as:
\[ n! = 1 \times 2 \times \cdots \times n \]
This problem also supports strings containing digits or other characters, using standard lexicographical order.
inputFormat
The input consists of a single line containing the string S. The string may include alphabets, digits, or other characters.
outputFormat
Output a single integer that represents the lexicographic rank of S among all its permutations in ascending order.
## sampleabc
1
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