Here is My Solution to the problem which has passed all the test cases

#include
using namespace std;

int kadane(int arr[], int n){

    int start = 0;
    int end = 0;
    int max_sum = 0;
    int sum = 0;

    while(end< n){
        
        if(sum > 0){
            sum = sum + arr[end];
        }else{
            sum = arr[end];
        }


        if(sum > max_sum){
            max_sum = sum;
        }
        end++;
    }
     
    return max_sum;

}

void circularsum(){
int t;
cin >> t;
while(t–>0){
int n;
cin>>n;
int arr[n];int sum =0;
for(int i =0; i<n; i++){
cin>>arr[i];
sum += arr[i];
arr[i]=-arr[i];
}
int neg_max = kadane(arr,n);

    cout << sum+neg_max<<endl;
}

}
int main() {
circularsum();
return 0;
}