include[HTML_REMOVED]
include[HTML_REMOVED]
using namespace std;
int main()
{
int n;
cin>>n;
int m;
while(cin>>m,m<=0);
int sum=0;
int k=0;
if(m>0)
{
for(int i=n;;i)
{
sum=sum+i;
k;
if(k==m)
break;
}
}
printf(“%d”,sum);
return 0;
}