CodeForces

#include <bits/stdc++.h>using namespace std;int main() {    int n, k; cin >> n >> k;    string s; cin >> s;    int cnt[30] = {0};    for (int i = 0; i < s.size(); i++) {        cnt[s[i] - 'a']++;    }    bool ok = true;    for (int i = 0; i < 26; i++) {        if (cnt[i] > k) {            ok = false; break;        }    }    if (ok) cout << "YES" << endl;    else cout << "NO" << endl;    return 0;}