python basics-loop

for loop:

a = [11,22,33,44]

for i in a:
print (i)

result:

11
22
33
44

while loop:

i=0
while i < 3: #i<3 is the loop condition. When the condition is true, the following loop body will be executed; when the condition is false, it will not be executed.
print (i)
i += 1

Result:

0
1
2

break and Continue:

i= 0
while i < 10:
print ("i->:",i)
if i == 5:
break #When i==5, exit all loops
i += 1

Result:

i->: 0
i->: 1
i->: 2
i->: 3
i->: 4
i->: 5
x=0
while x < 9:
for x in range(0,10):
if x ==6:
continue #when x== At 6 o'clock, jump out of the current loop and continue the next loop
                                                                  print("x->:", x)

Result:

x->: 0
x->: 1
x->: 2
x->: 3
x->: 4
x->: 5
x->: 7 #missingx->: 6
x->: 8
x->: 9

Others:

enumrate:

a = ["aa","bb","cc","dd"]

for i in enumerate(a,5): #The default number starts from 0, Can be changed manually
Print (i)

Result:

(5, 'aa')
(6, 'bb')
(7, 'cc')
(8, 'dd')

range :

1,

for n in range(1, 10):
print (n)

Result:

1
2
3
4
5
6
7
8
9

2 ,

for x in range(0,20,4):
print (x)

Result:

0
4
8
12
16
#Use 4 as step and print