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 1. 1 ≤ i, j ≤ N 2. S[i] = S[j], that is the i -th symbol of string S is equal to the j -th.
输入描述:
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.
输出描述:
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.
示例1
输入
great10<br />aaaaaaaaaa<br />
加载中...