Light oj 1214-Large Division (同余定理)

题目链接：http://lightoj.com/volume_showproblem.php?problem=1214

题意很好懂，同余定理的运用，要是A数被B数整除，那么A%B等于0。而A很大，那我就把A的每一位拆开，比如A是2341，那么2341=2000+300+40+1，然后你懂的...

#include <iostream>
#include <cstdio>
#include <cstring>
using namespace std;
char str[2005];
int main()
{
    int t;
    long long n;
    cin >> t;
    for(int ca = 1 ; ca <= t ; ca++) {
        cin >> str >> n;
        int len = strlen(str);
        long long temp = 0 , begin = 0;
        if(str[0] == '-')
            begin++;
        for(int i = begin ; i < len ; i++) {
            temp = (temp * 10 % n + (str[i] - '0')) % n;
        }
        cout << "Case " << ca << ": ";
        if(!temp)
            cout << "divisible
";
        else
            cout << "not divisible
";
    }
}