def maxSubArraySum(a,size):
    max_so_far = float('-inf')
    max_ending_here = 0
       
    for i in range(0, size): 
        max_ending_here = max_ending_here + a[i] 
        if (max_so_far < max_ending_here): 
            max_so_far = max_ending_here 
  
        if max_ending_here < 0: 
            max_ending_here = 0   
    return max_so_far 


import math

 
def main():
        T=int(input())
        while(T>0):
            
            n=int(input())
            
            arr=[int(x) for x in input().strip().split()]
            
            print(maxSubArraySum(arr,n))
            
            T-=1


if __name__ == "__main__":
    main()