//我覺得這題好像跟我理解的不太一樣啊T ^ T，有點郁悶?

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Description

There is a given string S consisting of N symbols. Your task is to find the number of ordered pairs of integers i and j such that

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1. 1?≤?i,?j?≤?N

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2. S[i]?=?S[j], that is the i-th symbol of string S is equal to the j-th.

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Input

The single input line contains S, consisting of lowercase Latin letters and digits. It is guaranteed that string S in not empty and its length does not exceed 105.

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Output

Print a single number which represents the number of pairs i and j with the needed property. Pairs (x,?y) and (y,?x) should be considered different, i.e. the ordered pairs count.

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Sample Input

Input

great10

Output

7

Input

aaaaaaaaaa

Output

100

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1 #include<stdio.h> 2 3 #include<string.h> 4 5 6 7 int t[100000]; 8 9 10 11 int main() 12 13 { 14 15 char s[100000]; 16 17 while(gets(s)) 18 19 { 20 21 double sum=0; 22 23 int l=strlen(s); 24 25 memset(t,0,sizeof(t)); 26 27 for(int i=0;i<l;i++) 28 29 { 30 31 t[s[i]]++; 32 33 } 34 35 for(int i='0';i<='z';i++) 36 37 { 38 39 sum+=(double)t[i]*t[i]; 40 41 } 42 43 printf("%.0lf\n",sum); 44 45 } 46 47 return 0; 48 49 } View Code

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轉載于:https://www.cnblogs.com/awsent/p/4266900.html

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