#include <stdio.h>
#include <string.h>

int line_sums[1010];

int main() {
    int T;
    int n, m;
    char linebuf[1010];
    scanf("%d", &T);
    for (int _ = 0; _ < T; _++) {
        scanf("%d %d", &n, &m);
        int line_odd_count = 0;
        memset(line_sums, 0, sizeof(line_sums));
        for (int i = 0; i < n; i++) {
            scanf("%s", linebuf);
            int cur_line_xor = 0;
            for (int j = 0; j < m; j++) {
                cur_line_xor ^= linebuf[j] - '0';
                line_sums[j] ^= linebuf[j] - '0';
            }
            if (cur_line_xor == 1) {
                line_odd_count++;
            }
        }

        int col_odd_count = 0;
        for (int j = 0; j < m; j++) {
            col_odd_count += line_sums[j];
        }

        printf("%d\n", col_odd_count > line_odd_count ? col_odd_count : line_odd_count);
    }
    return 0;
}