View Code of Problem 86

#include<iostream>
using namespace std;
int main(){
	long long  a,n;
	cin>>a>>n;
	long long k=a;
	long long sum=0;
	for(int i=0;i<n;i++){
		sum+=k;
		k=(k*10+a);
		//cout<<k<<endl;
	}
	cout<<sum;
}