Ques 3

#include <bits/stdc++.h>

using namespace std;
typedef long long ll;

int main()
{
    #ifndef ONLINE_JUDGE
        freopen("input.txt", "r", stdin);
        freopen("output.txt", "w", stdout);
    #endif

    int n;
    cin >> n;
    int mx = -1;
    int arr[n];

    for(int i = 0; i < n; i++){
        cin >> arr[i];
        mx = max(arr[i], mx);
    }

    int freq[mx] = {0};


    for(int j = 0; j < n; j++){
        freq[arr[j]]++;
    }

    int mergearr[n+2];
    int i = 0;

    for(int j = 0; j <= mx; j++)
    {
        if(freq[j] >= 1)
            mergearr[i++] = j;
        if(freq[j] > 1)
            printf("%d %d\n",j,freq[j]);
    }
    for(int j = 0; j < i; j++)
        cout << mergearr[j] << ' ';
    cout << endl;

    return 0;
}