#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <math.h>
int main(int argc, char* argv[])
{
int b[200];
int i,k,j,mul;
int remind;
int a,n;
while(scanf("%d %d",&a,&n) != EOF)
{
remind = 0;
k = 0;
for(i=n;i>=1;i--)
{
mul = a*i + remind;
b[k++] = mul % 10;
remind = mul / 10;
}
while(remind > 0)
{
b[k++] = remind % 10;
remind /= 10;
}
for(j=k-1;j>=0;j--)
printf("%d",b[j]);
printf("\n");
}
return 0;
}