UVA 11019 - Matrix Matcher

#include <bits/stdc++.h>

using namespace std;
#define rint register int
#define rll register long long
typedef long long ll;
const int maxn = 1e3 + 100;
const int base1 = 233, base2 = 2333;
char a[maxn][maxn], b[maxn][maxn];
unsigned long long ha[maxn][maxn], hb[maxn][maxn];


int main() {
    freopen("in.txt", "r", stdin);
    rint _;
    scanf("%d", &_);
    while (_--) {
        rint n, m, x, y;
        scanf("%d %d", &n, &m);
        for (rint i = 1; i <= n; i++)
            scanf("%s", a[i] + 1);
        scanf("%d %d", &x, &y);
        for (rint i = 1; i <= x; i++)
            scanf("%s", b[i] + 1);
        register unsigned long long p1 = 1, p2 = 1;
        for (rint i = 1; i <= x; i++) {
            p2 *= base2;
        }
        for (rint i = 1; i <= y; i++) {
            p1 *= base1;
        }
        for (rint i = 1; i <= x; i++) {
            for (rint j = 1; j <= y; j++) {
                hb[i][j] = (b[i][j] - 'a') + hb[i][j - 1] * base1 + hb[i - 1][j] * base2 -
                           hb[i - 1][j - 1] * base1 * base2;
            }
        }
        rint ans = 0;
        for (rint i = 1; i <= n; i++) {
            for (rint j = 1; j <= m; j++) {
                ha[i][j] = (a[i][j] - 'a') + ha[i][j - 1] * base1 + ha[i - 1][j] * base2 -
                           ha[i - 1][j - 1] * base1 * base2;
                if (i >= x && j >= y &&
                    hb[x][y] == ha[i][j] - ha[i - x][j] * p2 - ha[i][j - y] * p1 + ha[i - x][j - y] * p1 * p2) {
                    ans++;
                }
            }
        }
        printf("%d\n", ans);
    }

    return 0;
}