Code for Maximum Circular Sum failing on one test case

#1

My solution for the maximum circular sum is failing on one test case. Can anybody let me know the issue in the code?
`#include<bits/stdc++.h>
using namespace std;

int main() {
int t;
cin>>t;
while(t–) {
int n;
cin>>n;

	int sum=0;
	int flag=0;

	int arr[n];
	for(int i=0; i<n; i++) {
		cin>>arr[i];
		if(arr[i]>0) {
			flag=1;
		}
	}
	
	int m=arr[0];
	
	for(int i=0; i<n; i++) {
	    if(m< arr[i]) {
	        m= arr[i];
	    }	
	}

	if(flag==0){
		cout<<m<<endl;
	}
	
	else {

	for(int i=0;i<n;i++) {
		sum += arr[i];	
		arr[i]= -arr[i];
	}

	int currSum=0;
	int maxSum= 0;

	for(int i=0;i<n;i++) {
		currSum= max(currSum+arr[i], arr[i]);
		maxSum= max(maxSum, currSum);

	}
	//cout<<sum;

	maxSum= -((-sum)-maxSum);
	cout<<maxSum<<endl;
}
}

return 0;

}`

#2

Okay so I am able to figure out. We need to calculate max subarray for normal array as well. and then print cout<<max(maxSum,m)<<endl;