Translation d30 (with AC code POJ 28:sum number)

“ Ctrl AC！ Together AC！”

The original title is ：Sum Number

My translation ：

describe

Given a N Sequence of Numbers . How many numbers in the sequence are equal to the sum of two different numbers in the sequence .

Input

first line ： A positive integer N（N<=100）. The second line ：N A positive integer （<=100000）.

Output

An integer .

AC Code ：

#include<bits/stdc++.h>
using namespace std;
int num[105];
int sum[5000];
int main(){
	int n;cin>>n;
	for(int i=0;i<n;i++){
		cin>>num[i];
	}
	for(int i=0;i<n;i++){
		for(int j=i+1;j<n;j++){
			if(num[i]!=0&&num[j]!=0)
				sum[num[i]+num[j]]++;
		}
	}
	int ans=0;
	for(int i=0;i<n;i++){
		if(sum[num[i]]) ans++;
	}
	cout<<ans<<endl;
	return 0;
}

Thank you for reading ！！！

“ Ctrl AC！ Together AC！”