n=input().split()
X=int(n[0])
Y=int(n[1])
if(X%5==0):
if(X<Y):
B = Y-X-0.5
print(B)
if(X>Y):
print(Y)
else:
print(Y)
n=input().split()
X=int(n[0])
Y=int(n[1])
if(X%5==0):
if(X<Y):
B = Y-X-0.5
print(B)
if(X>Y):
print(Y)
else:
print(Y)