```
#include <bits/stdc++.h>
using namespace std;
int n, a[101];
int main(){
scanf("%d", &n);
for (int i = 1; i <= n; i++)
scanf("%d", &a[i]);
int ans = 0;
for (int i = 1; i <= n; i++){
bool ok = false;
for (int j = 1; j <= n; j++)
for (int k = 1; k <= n; k++)
if (i != j && i != k && j != k)
if (a[i] == a[j] + a[k])
ok = true;
if (ok)
ans++;
}
printf("%d", ans);
return 0;
}
```
by Pitiless_boy @ 2023-09-13 18:55:45