I solved this problem, but I get Wrong Answer.
The thing is that i couldn't possibly get Wrong Answer
if my solution to the problem was wrong. I would get
timeout. (notice the for(;;);).

Can anyone tell me what is wrong?



#include <stdio.h>

#define MAX 10000

int n, m;

int a[MAX], sol[MAX];

void readinput()
{
    int i;

#ifndef ONLINE_JUDGE
    freopen("multiple.in", "r", stdin);
    freopen("multiple.out", "w", stdout);
#endif

    scanf("%d", &n);
    for (i = 0; i < n; i++)
        scanf("%d", &a[i]);
}

void solve()
{
    int b[MAX], dince[MAX], use[MAX], i, j, suma, testsum;

    for (i = 0; i < n; i++)
    {
        if (a[i] % n == 0)
        {
            printf("1\n%d\n", a[i]);
            return;
        }
        b[i] = -1;
        dince[i] = -1;
    }
    for (i = 0; i < n; i++)
    {
        b[a[i] % n] = a[i];
        dince[a[i] % n] = -1;
        use[a[i] % n] = a[i];
        for (j = n - 1; j >= 0; j--)
            if (b[j] != -1 && b[(j + a[i]) % n] == -1)
            {
                b[(j + a[i]) % n] = (j + a[i]) % n;
                dince[(j + a[i]) % n] = j;
                use[(j + a[i]) % n] = a[i];
            }
    }
    m = 0;
    suma = 0;
    while (1)
    {
        sol[m++] = use[suma];
        if (dince[suma] == -1)
            break;
        suma = dince[suma];
    }
    testsum = 0;
    for (i = 0; i < m; i++)
        testsum = (testsum + sol[i]) % n;
    if (testsum != 0)
        for(;;);
    printf("%d\n", m);
    for (i = 0; i < m; i++)
        printf("%d\n", sol[i]);
}

void writeoutput()
{
#ifndef ONLINE_JUDGE
    fclose(stdin);
    fclose(stdout);
#endif
}

int main()
{
    readinput();
    solve();
    writeoutput();
    return 0;
}

ur output always is a multiple of N but some numbers may be used more
than once, so WA :)