Position in Fraction

You have a fraction . You need to find the first occurrence of digit c into decimal notation of the fraction after decimal point.

1 2 0

2

2 3 7

-1

code：

#include <iostream>
#include <cstdio>
#include <cstring>
using namespace std;
int main(){
    int n,m,c,i;
    scanf("%d%d%d",&m,&n,&c);
    int pos = -1;
    int fz = m,fm = n;
    i = 0;
    while(1){
        i++;
        fz *= 10;
        if(fz / fm == c){
            pos = i;
            break;
        }
        fz = fz % fm;
        if(i >= 100005) break;//限制循环节长度
    }
    printf("%d\n",pos);
    return 0;
}