title | comments |
---|---|
SPOJ 3410: SAMER08F - Feynman |
true |
How many squares a (4x4) square holds? the answer is-
16 (1x1) squares + 4 (2x2) squares, 9 (3x3) squares, 1 (4x4) squares
Meaning, the answer is
$$
\sum_{i=1}^{n} i^2 = 1^2 + 2^2 + 3^2 +...+ n^2 = \frac{n(n+1)(2n+1)}{6}
$$
#include<stdio.h>
int main()
{
int n,x;
while(scanf("%d",&n)&&n!=0)
{
x=(n*(n+1)*((2*n)+1))/6;
printf("%d\n",x);
}
return 0;
}