#include <iostream>
using namespace std;

int main(){
	char a;
	int n;
	cin>>a>>n;
	int count=0;
	for(int i=0;i<n;i++){
		string s(i+1,a);//字符串 a,aa,aaa.....
		count+=stoi(s);//将其转成整数
	}
	cout<<count;
	return 0;
}