HackerEarth Moving people problem solution

1. 1 X Y: Move every person that is currently residing in the grid, X column left of their cells and Y column above of their cells. If X is negetive, then move people abs(X) column right of their cells. Also, if Y is negative, then move people abs(Y) column down of their cells.
2. 2: Calculate the numbner of people that are currently living in the grid.

#include<bits/stdc++.h>
using namespace std;

const int maxn = 1005;
int n, m, x, y, z, k;

string str[maxn];
int csum[maxn][maxn];

int main()
{

    cin >> n >> m >> k;
    for(int i = 1; i <= n; i++) cin >> str[i];

    for(int i = 1; i <= n; i++){
        for(int j = 1; j <= m; j++){
            csum[i][j] = csum[i - 1][j] + csum[i][j - 1] - csum[i - 1][j - 1];
            if(str[i][j - 1] == '1') csum[i][j]++;
        }
    }

    int lft = 1, rgh = m, up = 1, dwn = n;
    bool flg = false;

    int mxlft = 1, mnrgh = m;
    int mxup = 1, mndwn = n;

    while(k--){
        int tp;
        scanf("%d", &tp);
        if(tp == 1){
            int x, y;
            scanf("%d %d", &x, &y);

            lft += x;
            rgh += x;

            up += y;
            dwn += y;

            mxlft = max(mxlft, lft);
            mnrgh = min(mnrgh, rgh);

            mxup = max(mxup, up);
            mndwn = min(mndwn, dwn);

        }
        else{

            if(mxlft > mnrgh || mxup > mndwn) printf("0n");
            else{
                int anss = csum[mndwn][mnrgh] - csum[mndwn][mxlft - 1] - csum[mxup - 1][mnrgh] + csum[mxup - 1][mxlft - 1];
                printf("%dn", anss);
            }

        }
    }


    return 0;
}