array pair divisibility problem

/*
Given an array of integers and a number k, write a function that returns true if given array can be divided into pairs such that sum of every pair is divisible by k.

Input:
The first line of input contains an integer T denoting the number of test cases. The T test cases follow. Each test case contains an integer n denoting the size of the array. The next line contains the n space separated integers forming the array. The last line contains the value of k.

Output:
Print "True" (without quotes) if given array can be divided into pairs such that sum of every pair is divisible by k or else "False" (without quotes).

Constraints:
1<=T<=100
2<=n<=10^5
1<=a[i]<=10^5
1<=k<=10^5

Example:
Input:
2
4
9 7 5 3
6
4
91 74 66 48
10

Output:
True
False
*/

#include <bits/stdc++.h>
using namespace std;

void isPairSumDivisibility(int s, int n, int k){
    if(s%k ==0 && n%2 ==0) cout<<"True\n";
    else cout<<"False\n";
}
int main() {
    int t; cin>>t; while(t--){
        int n,k,s=0; cin>>n; int a[n]; 
        for(int i=0; i<n; i++) {
            cin>>a[i];
            s=s+a[i];
        }
        cin>>k;
        isPairSumDivisibility(s,n,k);
    }
	return 0;
}