My solution:

include

using namespace std;

int main(){ ios::sync_with_stdio(0); cin.tie(0);

int n, q;
cin >> n >> q;
vector<vector<int>> no(n);
for(int i = 0; i<n; i++){
    int k;
    cin >> k;
    no[i].resize(k);
    for(int j = 0; j<k; j++){
        cin >> no[i][j];
    }
}
while(q-->0){
    int x, y;
    cin >> x >> y;
    cout << no[x][y] << '\n';
}

return 0;

}

I am not that familiar with pointers actually, so I used vectors instead.

return 0;

}

int main() { /* Enter your code here. Read input from STDIN. Print output to STDOUT */
int n, q; cin >> n >> q; // number of arrays and number of queries

vector<vector<int>> arr(n);

// input arrays
for (int i = 0; i < n; i++) {
    int k;
    cin >> k;   // size of this array
    arr[i].resize(k);
    for (int j = 0; j < k; j++) {
        cin >> arr[i][j];
    }
}

// answer queries
for (int i = 0; i < q; i++) {
    int M, N;
    cin >> M >> N;
    cout << arr[M][N] << endl;
}
return 0;

}

cin >> n >> q;
int** arr = new int*[n];
for(unsigned int h = 0; h < n; ++h)
{
    cin >> k;
    *(arr + h) = new int[k];
    for(unsigned m = 0; m < k; ++m) {cin >> *(*(arr + h)+ m);}
}
for(unsigned int h = 0; h < q; h++){cin >>i >>j; cout << *(*(arr + i)+ j) << endl;}

Here is my code

include

include

include

include

include

using namespace std;

int main() {

int n ;
cin >> n;
int q ;
cin >> q;
vector<vector<int>> arr(n);  

for (int i = 0; i < n; i++) {
    int k ;
    cin >> k;

    arr[i].resize(k);

    for (int j = 0; j < k; j++) {
        cin >> arr[i][j];
    }
}

for (int j = 0 ; j < q ; j++) {
    int x, y ;
    cin >> x >> y;
    cout << arr[x][y] << endl;
}
return 0;

}

Here is my code!

#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;


int main() {
    int num_arrays, num_queries, num_items, current_item, array_i, item_i;
    vector<int> current_array;
    scanf("%d %d", &num_arrays, &num_queries);
    vector<vector<int>> arrays;
    for (int i = 0; i < num_arrays; i++) {
        current_array = {};
        scanf("%d", &num_items);
        for (int item = 0; item < num_items; item++) {
            scanf("%d", &current_item);
            current_array.push_back(current_item);
        }
        arrays.push_back(current_array);
    }
    for (int i = 0; i < num_queries; i++) {
        scanf("%d %d", &array_i, &item_i);
        printf("%d", arrays[array_i][item_i]);
        if (i != num_queries - 1) {
            printf("\n");
        }
    }
    return 0;
}