# AtCoder Beginner Contest 183
# A-ReLU
# x = int(input())

# def main(value:int) -> int:
#     if value >= 0:
#         return value
#     else:
#         return 0

# print(main(x))




# B-Billiards
# SG = list(map(int, input().split()))
# point1 = [SG[0], SG[1]]
# point2 = [SG[2], SG[3]]

# def solve(point1:list, point2:list) -> float:
#     ans = point1[0] + ( point1[1] / (point1[1]+point2[1]) ) * (point2[0]-point1[0])
#     return ans

# print(solve(point1, point2))




# C-Travel