int main()
{
int x = 0, y = 0;
int t = 0;
scanf("%d",&x);
if((x >= 0) && (x < 1))
y = x * x;
if((x >= 1) && (x < 2))
y = x * x + 1;
if((x >= 2) && (x < 3))
y = t * t - 2 * t + 1;
printf("%d",y);
return 0;
}