# read string from keyboard into variable x
x = input("Enter a number: ")

# convert x to int and store it back in x again
x = int(x)

# read string from keyboard into variable y
y = input("Enter another number: ")

# convert y to int and store it back in y again
y = int(y)

# read string from keyboard into variable z
z = input("Enter another number: ")

# convert z to int and store it back in z again
z = int(z)

# print the sum of x + y + z
print("The sum of the three numbers is:", x + y + z)

# print the difference of x - y - z
print("The difference of the three numbers is:", x - y - z)