2025 04 19

# a,b=map(int,input().split())
# l=list(map(int,input().split()))
# list=[]
# t=sum(l[0:b])
# o=t
# list.append(o)
# for i in range(a-b):
#     o=o+l[b+i]-l[i]
#     list.append(o)
# print(max(list))

# a,b=map(int,input().split('x'))
# x=-b/a
# print('%.2f'%x)

# a,t=input().split("x")
# b,c=map(int,t.split("="))
# a=int(a)
# x=(c-b)/a
# print('%.2f'%x)