#include <stdio.h>
 int main(void)
 {
 	int x;
 	int ans;
 	
 	do{
 		scanf("%d", &x);
 		if (x == 0) break;
 		
 		ans = x*x+2*x-5;
 		
 		printf("%d\n", ans);
 	}while(-1000<=x && x<=1000 && x != 0);
 	
 	return(0);
 }