Revise paste Untitled

#include <iostream>
#include <vector>
#include <queue>
using namespace std;
typedef long long ll;

int main()
{
    int n, m;
    cin >> n >> m;
    int mat[n][m];
    for(int i = 0; i < n; i++) {
        for(int j = 0; j < m; j++) {
            mat[i][j] = -1;
        }
    }
    int R, K;
    cin >> R >> K;
    R--;
    K--;
    queue<int> Q;
    Q.push(R);
    Q.push(K);
    Q.push(0);
    mat[R][K] = 0;
    int biggest_number = 0;
    while(!Q.empty()) {
        int ci = Q.front();
        Q.pop();
        int cj = Q.front();
        Q.pop();
        int number = Q.front();
        Q.pop();
        biggest_number = max(biggest_number, number);
        if(ci + 1 < n and mat[ci + 1][cj] == -1) {
            Q.push(ci + 1);
            Q.push(cj);
            Q.push(number + 1);
            mat[ci + 1][cj] = number + 1;
        }
        if(ci - 1 >= 0 and mat[ci - 1][cj] == -1) {
            Q.push(ci - 1);
            Q.push(cj);
            Q.push(number + 1);
            mat[ci - 1][cj] = number + 1;
        }
        if(cj + 1 < m and mat[ci][cj + 1] == -1) {
            Q.push(ci);
            Q.push(cj + 1);
            Q.push(number + 1);
            mat[ci][cj + 1] = number + 1;
        }
        if(cj - 1 >= 0 and mat[ci][cj - 1] == -1) {
            Q.push(ci);
            Q.push(cj - 1);
            Q.push(number + 1);
            mat[ci][cj - 1] = number + 1;
        }
    }
    int chocolates = 0;
    
    for(int i = 0; i < n; i++) {
        for(int j = 0; j < m; j++) {
            if(mat[i][j] == biggest_number) {
                chocolates++;
            }
        }
       
    }
    cout << biggest_number << endl;
    cout << chocolates << endl;
    return 0;
}