HDU5832-CCPC Network race-high-precision redundancy

Title Address: http://acm.hdu.edu.cn/showproblem.php?pid=5832
The topic Two planets, one year 137 days, one year 73 days, give a day to ask is not at the same time is two planets in the first days. 0 represents the first day.
Thinking of solving problems
Because 137 and 73 are prime numbers, so the least common multiple is 10001, the problem is converted to a high-precision number of 10001 to take the remainder is equal to 0.
About high-precision redundancy. For example, 123 to 12, actually equals ((1%12*10+2)%12*10+3)%12=3, which is actually the process of simulating a division.
Code

#include <cstring>
#include <cstdio>
using namespace std;
#define MAXN 10005000
int A[MAXN];
int B[MAXN];
int Len;
Char STR[MAXN];
int main ()
{
    int i=1;
    while (scanf ("%s", str) ==1)
    {
        int tomod = 10001;
        int ans = 0;
        for (int j = 0; str[j]; j + +)
            ans = (ans * + (str[j]-' 0 '))% Tomod;
        if (ans)
            printf ("Case #%d:no\n", i++);
        else
            printf ("Case #%d:yes\n", i++);
    }
    return 0;
}