Python之条件判断和循环(入门4)

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http://www.cnblogs.com/why168888/p/6407755.html

本文出自:【Edwin博客园】

Python之条件判断和循环

1. Python之if语句

score = 75
if score >= 60:
    print 'passed'

2. Python之if-else

score = 55
if score >= 60:
    print 'passed'
else:
    print 'failed'

3. Python之if-elif-else

score = 85
if score >= 90:
    print 'excellent'
elif score >= 80:
    print 'good'
elif score >= 60:
    print 'passed'
else:
    print 'failed'

4. Python之for循环

L = [75, 92, 59, 68]
sum = 0.0
for x in L:
    sum = sum + x
print sum / 4

5. Python之while循环

sum = 0
x = 1
while x < 100:
    sum = sum + x
    x = x + 2
print sum

6. Python之break退出循环

sum = 0
x = 1
n = 1
while True:
    if n > 20:
        break
    sum = sum + x
    x = x * 2
    n = n + 1
print sum

7. Python之continue继续循环

sum = 0
x = 0
while True:
    x = x + 1
    if x > 100:
        break
    if x % 2 == 0:
        continue
    sum = sum + x
print sum

8. Python之continue继续循环

for x in [1, 2, 3, 4, 5, 6, 7, 8, 9]:
    for y in [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]:
        if x < y:
            print x * 10 + y