24 months ago

mg2002 • 40

#include <bits/stdc++.h>
#include <algorithm>
#include <stack>
using namespace std;
#define pb push_back
#define ll long long int
#define MAXN 1000001
#define MOD 1000000007

int main() {
    int n;
    cin >> n;
    string s;
    cin >> s;
    int freq[26] = {0};
    for (int i = 0; i < n; i++)
    {
        freq[s[i] - 'a']++;
    }
    int ans = 0;
    for (int i = 0; i < 26; i++)
    {
        ans += (freq[i] * freq[25 - i]);
    }
    cout << (ans / 2) << endl;

    return 0;
}

24 months ago

Rishabh • 0

Bhai OA ka pattern kya tha , mcq kis subjects se the??