python 求助
这段代码为什么死活不执行else后面的print语句呢？
# -*- coding: utf8 -*-
import random
a = 0
while a == 0:
x = random.randint(1,10)
y = random.randint(1,10)
print x,"+",y,"=",
shuru_desu = raw_input( )
desu = x + y
if desu != shuru_desu:
print ("No")
else:
print ("Yes")
