python while loop is nested for loop

while loop nest   

　　There is also the while loop while loop

while nested format

1  the while   Condition 1:
 2      when the condition 1 is satisfied, repeating events
 . 3      
. 4      the while Condition 2:
 . 5          when the two conditions are satisfied, repeating events

Multiplication table

1 i= 1
2 while i<= 9:
3     j = 1
4     while j <= i:
5         print("%d*%d=%-2d" % (j, i, i*j ), end= " ")
6         j  += 1
7     print("\n")  # 换行
8     i += 1

for loop

　　The for loop can iterate over any sequence of items, such as list

break 和 continue 

The role of break: an immediate end to break the cycle where

Action continue to: continue to satisfy the conditions that skip one cycle, then the next cycle performed

break and continue in a cycle can only be used, can not be used alone,

In the nest cycle, only one cycle of recent work.

 

for loop format:

for   the temporary variables   in    the need to traverse the object or variables: 
    cyclic code is executed when the condition is satisfied

x = [1,2,3,4,5,6]
for i in x:
    print(i)