# age = int(input("ENTER YOUR AGE : "))
# if(age>=18):
# print("yes")
# else:
# print("no")
#================================================================z5
num1 = int(input("Enter the first number : "))
num2 = int(input("Enter the second number : "))
num3 = int(input("Enter the third number : "))
num4 = int(input("Enter the fourth number : "))
if num1>num2 and num1>num3 and num1>num4 :
print("greatest number is : ",num1)
elif num2>num1 and num2>num3 and num2>num4 :
print("greatest number is : ",num2)
elif num3>num1 and num3>num2 and num3>num4 :
print("greatest number is : ",num3)
else :
print("greatest number is : ",num4)
#=========================================================================