If in for Loop Break Start Loop Again

Break, Keep, and Else Clauses on Loops in Python

A quick overview of how to write better Python loops

Photo by Chris Ried on Unsplash

Loops in Python

• for loop
• while loop

Let's larn how to use control statements like intermission, continue, and else clauses in the for loop and the while loop.

Topics covered in this story (Paradigm source: Author)

'for' Statement

The for statement is used to iterate over the elements of a sequence (such as a string, tuple, or listing) or any other iterable object. -python docs

                          for              item              in              iterable:
              suite          

• The iterable is evaluated only once. An iterator is created for the event of that iterable.
• The suite is then executed once for each detail provided by the iterator, in the social club returned past the iterator.
• When the items are exhausted, the loop terminates.

Example 1. 'for' loop

                          for              i              in              range(one,vi):
              print (i)
              '''
Output:
1
2
iii
iv
5
'''                      

The for loop may have control statements like pause andgo along, or the else clause.

There may exist a situation in which you may demand to exit a loop completely for a particular condition or you want to skip a part of the loop and offset the next execution. The for loop and while loop have control statements suspension and go along to handle these situations.

'break' Statement

The break statement breaks out of the innermost enclosing for loop.

A break argument executed in the first suite terminates the loop without executing the else clause's suite.

The break statement is used to terminate the execution of the for loop or while loop, and the control goes to the argument after the body of the for loop.

Image source: Author

Case 2. Using the 'break' statement in a 'for' loop

• The for loop volition iterate through the iterable.
• If the particular in the iterable is 3, it volition break the loop and the control will go to the statement subsequently the for loop, i.east., print ("Outside the loop").
• If the item is not equal to 3, it will print the value, and the for loop will proceed until all the items are wearied.

                          for              i              in              [i,ii,three,iv,5]:
              if              i==three:
              suspension
              print (i)
impress ("Outside the loop")
              '''
Output:
one
2
Outside the loop
'''                      

Instance 3. Using the 'break' statement in a 'for' loop having an 'else' clause

A break statement executed in the first suite terminates the loop without executing the else clause's suite.

Image source: Writer

Example:

In the for loop, when the condition i==3 is satisfied, it volition interruption the for loop, and the command will become to the statement after the body of the for loop, i.e., impress ("Outside the for loop").

The else clause is also skipped.

                          for              i              in              [ane,2,3,iv,5]:
              if              i==3:
              break
              impress (i)
              else:
              print ("for loop is done")
print ("Outside the for loop")
                '''
Output:
1
2
Outside the for loop
'''              
                      

'continue' Statement

The continue argument continues with the side by side iteration of the loop.

A go along statement executed in the first suite skips the remainder of the suite and continues with the next item or with the else clause, if there is no next item.

Example 4. Using the 'continue' argument in a 'for' loop

• The for loop volition iterate through the iterable.
• If the particular in the iterable is 3, it volition keep the for loop and won't execute the rest of the suite, i.east., print (i).
• And so element 3 volition be skipped.
• The for loop will continue execution from the adjacent element.
• The else clause is besides executed.

                          for              i              in              [i,2,3,4,5]:
              if              i==3:
              go on
              print (i)
              else:
              print ("for loop is washed")
print ("Outside the for loop")
                '''
1
ii
iv
5
for loop is done
Outside the for loop
'''              
                      

Image source: Author

'else' Clause in 'for' Loop

Loop statements may have an else clause. It is executed when the for loop terminates through exhaustion of the iterable — but not when the loop is terminated by a intermission argument.

Example 5. Using the 'else' clause in a 'for' loop

The else clause is executed when the for loop terminates later the exhaustion of the iterable.

                          for              i              in              [one,2,3,four,5]:
              print (i)
              else:
              print ("for loop is washed")
impress ("Outside the for loop")
                '''
1
2
3
4
5
for loop is washed
Outside the for loop
'''              
                      

Example half dozen. Using the 'else' clause in a 'for' loop with the 'break' statement

The else clause is not executed when the for loop is terminated past a break statement.

                          for              i              in              [1,ii,3,iv,5]:
              if              i==iii:
              suspension
              print (i)
              else:
              print ("for loop is done")
impress ("Outside the for loop")
                '''
1
2
Outside the for loop
'''              
                      

Example seven. Using the 'else' clause in a 'for' loop with the 'continue' argument

The else clause is too executed.

                          for              i              in              [one,2,3,4,v]:
              if              i==3:
              continue
              print (i)
              else:
              impress ("for loop is done")
print ("Exterior the for loop")
                '''
one
ii
four
5
for loop is done
Outside the for loop
'''              
                      

Example viii. Using the 'suspension' statement and 'else' clause in a 'for' loop

Search the particular element in the list. If it exists, break the loop and return the index of the element; else return "Not found."

            l1=[i,3,5,vii,9]
              def              findindex(x,l1):
              for              alphabetize,particular              in              enumerate(l1):
              if              item==10:
              render              index
              break
                else:
              return "Not institute"impress (findindex(5,l1))
              #Output:2print (findindex(10,l1))
              #Output:Not found          

'while' Loop

The while statement is used for repeated execution as long every bit an expression is true. — python docs

                          while              expression:
              suite
              else:
              suite          

This repeatedly tests the expression and, if it is true, executes the first suite. If the expression is false (which it may be the first fourth dimension it is tested) the suite of the else clause, if nowadays, is executed and the loop terminates.

Example 9. Using the 'else' clause in a 'while' loop

The while loop is executed until the condition i<v is False.

The else clause is executed afterward the condition is False.

            i=0
              while              i<5:
              print (i)
              i+=1
              else:
              impress ("Element is not less than five")
                '''
Output:
0
1
ii
3
four
Element is not less than five
'''              
                      

Image Source:Writer

'break' Statement

A break statement executed in the first suite terminates the loop without executing the else clause's suite.

Case 10. Using the 'break' argument and 'else' clause in a 'while' loop

The break statement terminates the loop and the else clause is not executed.

            i=0
              while              i<5:
              print (i)
              i+=one
              if              i==3:
              break
else:
              print ("Element is not less than 5")
                '''
Output:
0
1
2
'''              
                      

Image Source:Author

'continue' Statement

A go along argument executed in the outset suite skips the residual of the suite and goes back to testing the expression.

Example 11. Using the 'continue' statement and 'else' clause in a 'while' loop

The go along argument skips the part of the suite when the status i==3 is Truthful. The control goes back to the while loop once again.

The else clause is also executed.

            i=0
              while              i<five:
              impress (i)
              i+=1
              if              i==three:
              go on
else:
              print ("Element is not less than v")
                '''
Output:
0
1
2
iii
four
Element is non less than 5
'''              
                      

Prototype Source:Author

Decision

• Python version used is 3.8.i.
• The intermission statement volition stop the loop (both for and while). The else clause is non executed.
• The continue statement will skip the rest of the suite and continue with the next item or with the else clause, if there is no side by side item.
• Theelse clause is executed when the for loop terminates after the exhaustion of the iterable.

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Source: https://betterprogramming.pub/break-continue-and-else-clauses-on-loops-in-python-b4cdb57d12aa