Wangpeng is good at drawing. Now he wants to say numbers like “521” to his girlfriend through the game draw something.
Wangpeng can’t write the digit directly. So he comes up a way that drawing several squares and the total area of squares is the number he wants to say.
Input all the square Wangpeng draws, what’s the number in the picture?

There are multiple test cases.
For each case, the first line contains one integer N(1≤N≤100) indicating the number of squares.
Second line contains N integers ai(1≤ai≤100)represent the side length of each square. No squares will overlap.
Input ends with N = 0.

For each case, output the total area in one line.

4
1 2 3 4
3
3 3 3
0

30
27

2012 Asia JinHua Regional Contest

#include <cstdio>
#include <cstring>
#include <iostream>
using namespace std;

int main()
{
	int n, sum;
	while(scanf("%d", &n), n)
	{
		int a;
		sum=0;
		for(int i=0; i<n; i++)
		{
			scanf("%d", &a);
			sum+=a*a;
		}
		printf("%d\n", sum);
	}
	return 0;
}