1063A - Oh Those Palindromes - CodeForces Solution

#include <bits/stdc++.h>
using namespace std;
#define int long long
#define M 1000000007
#define inf 1e9
#define ff first
#define ss second
#define pb push_back
#define ppb pop_back
#define cy cout << "YES\n";
#define cn cout << "NO\n";
#define minus cout << "-1\n";
#define fo(a, b) for (auto i = a; i < b; ++i)
#define nfo(a, b) for (auto i = a; i >= b; --i)
#define jfo(a, b) for (auto j = a; j < b; ++j)
#define njfo(a, b) for (auto j = a; j >= b; --j)

class solution
{
public:
    void solve()
    {
        int n;
        cin >> n;
        unordered_map<char, int> mp;
        fo(0, n)
        {
            char x;
            cin >> x;
            mp[x]++;
        }
        for(auto it : mp) fo(0,it.ss) cout << it.ff;
        
    }
};

int32_t main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);

    int t{1}, x{1};
    // cin>>t;
    while (t--)
    {
        x++;
        solution a;
        a.solve();
    };
}