#coding:utf-8

def max_array(lst):
    """()
    
    python  :qq:1465376564  
    python
    O(n)
    """
    this_sum = 0
    max_sum = 0
    for item in lst:
        this_sum += item
        if this_sum > max_sum:
            max_sum = this_sum
        elif this_sum < 0:
            this_sum = 0
    return max_sum

test_lst = [-2,11,-4,13,-5,-2]
print(max_array(test_lst))