pepper and even continguous sub array

/*
You have an array of length N. A subarray is called Interesting if it contains only even numbers. You have to  find the maximum length of
such Interesting subarray.
Input
First line contains T , denoting number of test cases.
Each test case contains two lines:
    - First line contains an integer N denoting the size of the array.
    - Second line contains N space seperated integers denoting the value of array elements.

Ouput:
For each test case, print the maximum length of Interesting subarray. If no such subarray exist,print -1.

Input Constraints:

1≤T≤10

1≤N≤105

1≤A[i]≤106

Note:

The input and output is handled by the code itself. You are just supposed to correct the function.

SAMPLE INPUT 
1
4
5 2 4 7
SAMPLE OUTPUT 
2
*/


#include <bits/stdc++.h>
#define ll long long int
using namespace std;



int main(){
    ll t; cin>>t; while(t--){
        ll n; cin>>n;
        ll a[n]; for(ll i=0; i<n;i++){
            cin>>a[i];
        }
        ll maxlen=0, len=0;
        for(ll i=0; i<n; i++){
               if(a[i]%2 == 0){
                   len++;
               }
               else
               {
                   if(len>maxlen)
                       maxlen=len;
                       len=0;
                   
               }
            }
            if(len>maxlen) maxlen=len;
            if(maxlen) cout<<maxlen<<endl;
            else cout<<-1<<endl;
    }
}