嗯同余~~(楼下说写题解加深印象)~~

#include<stdio.h>
#include<iostream>
using namespace std;
typedef long long ll;
int main()
{
	ll a,b,c,ans;
	while(cin>>a>>b>>c)
	{
		ans=((a%c)*(b%c))%c;
		cout<<ans<<endl;
	}
	return 0;
}