```
#include <cstdio>
#include <algorithm>
using namespace std;
void readInt(int &n){
int sign = 1;
char c;
bool found = false;
n = 0;
while(true){
c = getc(stdin);
switch(c){
case '-' :
sign = -1;
found = true;
break;
case ' ':
if(found) goto jump;
break;
case '\n':
if(found) goto jump;
break;
default:
if(c>='0' && c<='9'){
n = n*10+c-'0';
found = true;
}else goto jump;
break;
}
}
jump:
n *= sign;
}
int szB,szC,contB[1000000],contC[1000000];
int B[1000000],C[1000000];
int main(){
int N;
readInt(N);
int A[N];
for(int i = 0;i<N;++i)
readInt(A[i]);
szB = szC = 0;
for(int a = 0;a<N;++a)
for(int b = 0;b<N;++b)
for(int c = 0;c<N;++c)
B[szB++] = A[a]*A[b]+A[c];
for(int d = 0;d<N;++d)
if(A[d]!=0)
for(int e = 0;e<N;++e)
for(int f = 0;f<N;++f)
C[szC++] = A[d]*(A[e]+A[f]);
sort(B,B+szB);
sort(C,C+szC);
int n = 1,m = 1;
contB[0] = contC[0] = 1;
for(int i = 1;i<szB;++i){
if(B[i]!=B[n-1]){
B[n] = B[i];
contB[n] = 1;
++n;
}else ++contB[n-1];
}
for(int i = 1;i<szC;++i){
if(C[i]!=C[m-1]){
C[m] = C[i];
contC[m] = 1;
++m;
}else ++contC[m-1];
}
long long ans = 0;
for(int i = 0,j = 0;i<n && j<m;){
if(B[i]==C[j]) ans += (long long)contB[i]*contC[j];
if(B[i]>C[j]) ++j;
else if(B[i]<C[j]) ++i;
else{
++i;
++j;
}
}
printf("%lld\n",ans);
return 0;
}
```

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