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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