zoj 2548 Prerequisites?

#include<stdio.h>#include<string.h>int main(){    int k, m;    while (scanf("%d", &k), k)    {        scanf("%d", &m);        int selected[10000];        memset(selected, 0, 10000 * sizeof(int));        int sel, pass = 1;        while (k--)        { scanf("%d", &sel); selected[sel] = 1;        }        int c, r;        while (m--)        { scanf("%d %d", &c, &r); int mapped = 0; while (c--) {     scanf("%d", &sel);     if (selected[sel])         mapped++; } if (mapped < r)     pass = 0;        }        printf(pass ? "yesn" : "non");    }    return 0;}