Python Loop Control Statement
Table Of Contents:
- What Is Loop Control Statement?
- Break Statement.
- Continue Statement.
- Pass Statement.
(1)What Is A Loop Control Statement?
- When you want to get out of the loop in between you can use Loop Control Statements.
Loop will run as many times as the condition is satisfying.
- But, python provides us the ways to skip some iterations or stop the execution in between.
(2) Break Statement
- The Break statement stops the execution and brings the control out of the loop.
- You put some conditions and write a Break statement inside the loop.
If that condition is satisfying the Break statement will be executed and it will come out of the loop.
Break Syntax:
break
Note:
- You only need to write the ‘break’ keyword to break the execution of the loop.
Example-1
numbers = [1,2,3,4,5,6,7,8,9,10]
for i in numbers:
if i == 6:
break
print(i)
Output:
1
2
3
4
5
Note:
- In this program, the for loop will break when it encounters i == 6.
- And it will come out of the loop.
Example-2
number = 45
while number > 0:
number = number // 2
print(number)
if number == 1:
break
Output:
22
11
5
2
1
Note:
- In this program, when the number is getting 1 the while loop will break.
- And it will come out of the loop.
(3) Continue Statement
- Continue statement is used to skip the current iteration when the condition is met and allows the loop to continue with the next iteration.
- It does not bring the control out of the loop and unline the break statement.
Continue Syntax:
continue
Note:
- You only need to write the ‘continue’ keyword to skip the current execution of the loop.
Example-1
numbers = [1,2,3,4,5,6,7,8,9,10]
for i in numbers:
if i == 6:
continue
print(i)
Output:
1
2
3
4
5
7
8
9
10
Note:
- In this program, when the number is getting 1 , the for loop will skip the current execution.
- And it go to the next iteration and print.
- You can see the number 6 is not printed.
Example-2
var = 10
while var > 0:
var = var - 1
if var == 5:
continue
print('Current variable value :', var)
Output:
Current variable value : 9
Current variable value : 8
Current variable value : 7
Current variable value : 6
Current variable value : 4
Current variable value : 3
Current variable value : 2
Current variable value : 1
Current variable value : 0
Note:
- While loop will not execute when the number is 5.
- It will skit the code below the continue statement.
(4) Pass Statement
- Sometimes you only declare the functions and in a later stage, you will implement its body.
- At that time without a function body, it will give you an error.
- Hence, the ‘pass’ keyword is helpful when the function body is not present.
Pass Syntax:
pass
Example-1
def addition():
Output:
File "<ipython-input-16-8c308f48e9a2>", line 1
def addition():
^
SyntaxError: unexpected EOF while parsing
Example-2
def addition():
pass
Note:
- Here you can use the ‘pass’ keyword to avoid an error message.
- In a later stage, you can implement the function body.
Example-3
numbers = [1,2,3,4,5]
for i in numbers:
if i == 3:
pass
print(i)
Output:
1
2
3
4
5
Note:
- Here the ‘pass’ keyword will not do anything.
- It will not cause any changes to the flow of execution, it will just pass by..