我的编码中“ def”的语法错误无效。

Question

这是我的代码：我不确定是什么问题。 它说“ def sub”上的语法无效。 我到处都看过，据我所知，它已正确格式化为python 3

def add():
        print ("Enter the two numbers to Add")
        A=int(raw_input("Enter A: "))
        B=int(raw_input("Enter B: "))
        return A + B 

def sub():
        print ("Enter the two numbers to Subtract")
        A=int(raw_input("Enter A: "))
        B=int(raw_input("Enter B: "))
        return A - B

def mul():
        print ("Enter the two numbers to Multiply")
        A=int(raw_input("Enter A: "))
        B=int(raw_input("Enter B: "))
    return A * B

def div():
        print ("Enter the two number to Divide")
        A=float(raw_input("Enter A: "))
        B=float(raw_input("Enter B: "))
        return A / B

print ("1: ADD")
print ("2: SUBTRACT")
print ("3: MULTIPLY")
print ("4: DIVIDE")
print ("0: QUIT")

while True:

    CHOICE = int(raw_input("ENTER THE CORRESPONDING NUMBER FOR CALCULATION ")) 

    if CHOICE == 1: 
        print ('ADD TWO NUMBERS:')
        print add()

    elif CHOICE == 2:
        print ('SUBTRACT TWO NUMBERS')
        print sub()

    elif CHOICE == 3:
        print ('MULTIPLY TWO NUMBERS')
        print mul()

    elif CHOICE == 4:
        print ("DIVIDE TWO NUMBERS")
        print div()

    elif CHOICE == 0:
        exit()
    else:
        print ("The value Enter value from 1-4")

Answer 1

所有的打印像：

print add()

缺少括号。 他们应该是：

print(add())

所有打印均相同