Python for loop and while loop

 

#!pyton2
#-*- coding:utf-8 -*-

for letter in "Python":
    print "Current letter is:",letter
    
fruits=["apple","mango","pear"]

for fruit in fruits:
    print fruit
    
for index in range(len(fruits)):
        print fruits[index]

> python2 test.py
Current letter is: P
Current letter is: y
Current letter is: t
Current letter is: h
Current letter is: o
Current letter is: n
apple
mango
pear
apple
mango
pear

 

numbers=[1,2,3,4,5]
odd=[]
even=[]

while len(numbers)>0:
    number=numbers.pop()
    if number%2==0:
        even.append(number)
    else:
        odd.append(number)

print "numbers: ",numbers
print "odd :" ,odd
print "even:",even

numbers:  []
odd : [5, 3, 1]
even: [4, 2]

#break and continue

i=1
while i<10:
    i+=1
    if i%2 >0:
        continue
    print i
    
i=1
while 1:
    print i
    i+=1
    if i>4:
        break

2
4
6
8
10
1
2
3
4

 

#while,else

while count<3:
    print count," is less than 3"
    count+=1
else:
    print count, "is not less than 3"

#死循环    
flag=1
while flag==1:
    print "True!"


0  is less than 3
1  is less than 3
2  is less than 3
3 is not less than 3
True!
True!
True!
True!
True!
True!
True!

 

#!python2
#-*- coding:utf-8 -*-

def test_fun(num,step):
    i=0
    numbers=[]
    while i<num:
        print "At the top i is %d " %i
        numbers.append(i)
    
        i=i+step
        print "Numbers now: ",numbers
        print "At the bottom i is %d " % i
    
    print "The numbers:"
    for n in numbers:
        print n
        
def test_fun2(num,step):
    numbers=[]
    for i in range(0,num,step):
        print "At the top i is %d" %i
        numbers.append(i)
        print "Numbers now:", numbers
        
    print "The numbers:"
    for index in range(len(numbers)):
        print numbers[index]
        

def find_prime(start_num,end_num):
    for num in range(start_num,end_num):
        for i in range(2,num):
            if num%i==0:
                print "%d = %d * %d" %(num,i,num/i)
                break;        
        else:
            print "%d is a prime" % num
        

> python2
Enthought Canopy Python 2.7.11 | 64-bit | (default, Jun 11 2016, 11:33:47) [MSC v.1500 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> from ex33_2 import *
>>> find_prime(10,20)
10 = 2 * 5
11 is a prime
12 = 2 * 6
13 is a prime
14 = 2 * 7
15 = 3 * 5
16 = 2 * 8
17 is a prime
18 = 2 * 9
19 is a prime
>>> test_fun(8,4)
At the top i is 0
Numbers now:  [0]
At the bottom i is 4
At the top i is 4
Numbers now:  [0, 4]
At the bottom i is 8
The numbers:
0
4
>>> test_fun2(8,4)
At the top i is 0
Numbers now: [0]
At the top i is 4
Numbers now: [0, 4]
The numbers:
0
4