#include<stdio.h>

int n,ans,a[21],s[21];

int main()
{
	freopen("fly.in","r",stdin);
	freopen("fly.out","w",stdout);
	int i,j,k,l;
	scanf("%d",&n);
	for(i=1;i<=n;i++)
	{
		scanf("%d",&a[i]);
		s[i]=s[i-1]+a[i];
	}
	for(i=1;i<=n;i++)
	{
		for(j=i+1;j<=n;j++)
		{
			for(k=j+1;k<=n;k++)
			{
				for(l=k+1;l<=n;l++)
				{
					if(s[i-1]+s[n]-s[l-1]==s[k-1]-s[j-1]&&s[j-1]-s[i-1]==s[l-1]-s[k-1])
						ans++;
				}
			}
		}
	}
	printf("%d\n",ans);
	return 0;
}