Help bài này với mn c++ nhé!

#include <bits/stdc++.h>
using namespace std;
#define ll long long
ll n, mx = 0;
string s;
char c;
map<char, ll> cnt;
int main()
{
    cin >> n;
    cin >> s;
    for (char c: s)
    {
        cnt[c]++;
    }
    for (auto i: cnt)
    {
        mx = max(mx , i . second);
        if (mx == i . second)
        {
            c = i . first;
        }
    }
    cout << c;
}

#include <bits/stdc++.h>
#define ll long long
using namespace std;
int n,k,m;
string st;
map <int,int> d;
signed main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    freopen("BAI2.INP","r",stdin);
    freopen("BAI2.OUT","w",stdout);
    cin>>n;
    cin>>st;
    int nk=0;
    for(int i=0;i<st.size();i++)
    {
        d[st[i]]++;

    }
    char l='a';
    for(char i='a';i<='z';i++)
    {
       if(d[i]>d[l])
       {
           l=i;
       }
    }
    cout<<l;
    return 0;
}