27 lines
428 B
C++

#include<cstdio>
#include<cstring>
int f[51][5001];
int main()
{
int n,i,a[51],t=0,j;
scanf("%d",&n);
for(i=1;i<=n;i++)
{
scanf("%d",&a[i]);
t=t+a[i];
}
if (t%2!=0) printf("0");
else
{
memset(f,0,sizeof(f));
f[0][0]=1;
for(i=1;i<=n;i++)
for(j=0;j<=t/2;j++)
{
f[i][j]=f[i-1][j];
if (j-a[i]>=0) f[i][j]=f[i][j]+f[i-1][j-a[i]];
}
printf("%d",f[n][t/2]/2);
}
}