1037.Check a Sudoku

#include <cstdio>
#include <cstdlib>
#include <iostream>
using namespace std;

bool fr[9][10];
bool fc[9][10];
bool fb[9][10];
int a[9][9];

bool check() {
    int i, j;
    for (i = 0; i < 9; i++)
        for (j = 0; j < 10; j++)
            fr[i][j] = fc[i][j] = fb[i][j] = false;
    for (i = 0; i < 9; i++) {
        for (j = 0; j < 9; j++) {
            if (fr[i][a[i][j]] || fc[j][a[i][j]] || fb[i / 3 * 3 + j / 3][a[i][j]])
                return false;
            fr[i][a[i][j]] = fc[j][a[i][j]] = fb[i / 3 * 3 + j / 3][a[i][j]] = true;
        }
    }
    return true;
}

int main(int argc, char* argv[]) {
    int i, j, k, cas;

    scanf("%d", &cas);
    for (k = 1; k <= cas; k++) {
        for (i = 0; i < 9; i++)
            for (j = 0; j < 9; j++)
                scanf("%d", &a[i][j]);
        printf("Case %d:\n", k);
        printf("%s\n", check() ? "Yes!" : "No!");
    }

    return 0;
}