544A - Set of Strings - CodeForces Solution

#include<bits/stdc++.h>
using namespace std;
int k;
string ans[30], s;
int main()
{
    int cnt = 1, flag = 0, hash[400];
    cin >> k >> s;
    int len = s.length();
    memset(hash, 0, sizeof(hash));
    for (int i = 0; i < len; i++){
        if (!hash[s[i]]){
            hash[s[i]] = 1;
            ans[cnt++] += s[i];
        }
        else if (hash[s[i]] || s[i] == s[i - 1])
            ans[cnt - 1] += s[i];
        if (cnt == k + 1){
            for (int j = i + 1; j < len; j++)
                ans[cnt - 1] += s[j];
            flag = 1;
            break;
        }
    }
    if (!flag) {
        printf("NO\n");
    }
    else{
        printf("YES\n");
        for (int i = 1; i < cnt; i++)
            cout << ans[i] << endl;
    }
    return 0;
}