import sys def input(): return sys.stdin.readline().rstrip() def ii(f=int): return f(input()) def mi(f=int): return map(f, input().split()) def li(f=int): return list(map(f, mi())) T = li() t = 0 f = True for i in range(7): if T[i] == -1: f = False t += T[i] if(f and t <= 6000):print(6000 - t) else: print(-1)