s=[]
for i in range(12):
    s.append(int(input()))
ck=0
mm=0
month=1
for i in s:
    ck+=300
    ck-=i
    if ck<0:
        print('-',str(month))
        break
    mm+=(int(ck//100))
    ck=ck%100
    month+=1
else :
    mm=mm*120+ck
    print(mm)