Python’添加’功能问题：为什么这不起作用？

我刚刚开始学习 Python,我是一个绝对的新手.

我开始学习函数了,我写了这个简单的脚本：

def add(a,b):   
    return a + b

print "The first number you want to add?"
a = raw_input("First no: ")
print "What's the second number you want to add?"
b = raw_input("Second no: ")

result = add(a,b)

print "The result is: %r." % result

脚本运行正常,但结果不是总和.即：如果我为’a’输入5,为’b’输入6,结果将不是’11’,而是56.如下：

The first number you want to add?
First no: 5
What's the second number you want to add?
Second no: 6
The result is: '56'.

任何帮助,将不胜感激.

解决方法

raw_input返回string,需要将其转换为int

def add(a,b):   
    return a + b

print "The first number you want to add?"
a = int(raw_input("First no: "))
print "What's the second number you want to add?"
b = int(raw_input("Second no: "))

result = add(a,b)

print "The result is: %r." % result

输出：

The first number you want to add?

First no: 5
What's the second number you want to add?

Second no: 6
The result is: 11.