Submission #1758764

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Source Code Expand

#include <iostream>
#include <algorithm>
#include <string>

using namespace std;

string str;
int ap[256];

int main ()
{
    cin >> str;

    for (int i = 0; i < str.size (); ++i)
        ++ap[str[i]];

    long long ans = 1LL * str.size () * (str.size () - 1) / 2LL;
    for (int i = 'a'; i <= 'z'; ++i)
        ans -= 1LL * ap[i] * (ap[i] - 1) / 2LL;

    cout << ans + 1 << '\n';

    return 0;
}

Submission Info

Judge Result