code1083，Codeforces Round #158 (Div. 2) A - Adding Digits

題目：?http://codeforces.com/contest/260/problem/A

思路：a%b==0 => a*10^n%b==0

這題一開始忽略了一句話??If there are multiple possible answers, print any of them.

code1083，想了半天覺得答案不只一種啊

然后看到n的范圍就知道這題不可能一位位算

#include <iostream>
#include <cstdlib>
using namespace std;int a,b,n;
int main()
{cin >> a>>b>>n;a*=10;int flag=0;for(int i=0;i<10;i++){if(a%b==0) {flag=1;    break;}a++;}if(flag){cout << a;for(int i=0;i<n-1;i++){cout<<"0";}cout << endl;}else{cout << "-1"<<endl;}
return 0;
}

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