# 1912 연속합

n = int(input())
data = list(map(int,input().split()))

result = [0]*n
result[0] = data[0]

tmp=data[0]
for i in range(1,n):
  tmp= tmp+data[i]

  if tmp<0:
    tmp = 0 
  
  result[i]=tmp 


if max(data)<0 :
  print(max(data))
else:
  print(max(result))