Break, Continue, Pass and Else Statements in Python

 

Working With Break, Continue, Pass and else Statements in Python

 

For and while loop allows to repeat instruction until final result do not get. Some times due to some external factors influence on program. In this situation loop should be completely exit and skip part of loop before continue it. This is controlled with break, continue and pass statements in Python.

1.         Break Statement:

Break statement helps to exit a loop when an external factors are triggered.  The break statement is written within the block of code under loop statement after if statement.

Syntax:

                        break

Example:

#breal statement in while loop

string1="hello"

ch=0

while ch<len(string1):

    if string1[ch]=='o':

        ch=ch+1

        break

    print(" Current letters:" ,string1[ch])

    ch+=1

O/P:

Current letters: h

 Current letters: e

 Current letters: l

 Current letters: l

 In above example first string is created then ch variable is initialized with 0. by using while loop whole string is checked with len function. Then by using if statement character in string is checked. If character is exactly equals to ‘o’ then loop iteration will stops and current characters in loop will be executed and printed on screen.

Another Example:

A=10

while A>=1:

    print(" A=", A)

    A=A-1

    if A==5:

        break

        print("Out of Loop")

O/P:

A=10

A=9

A=8

A=7

A=6

Out of Loop


    2.         Continue Statement:

The continue statement in python is used to skip the rest of the code in the loop for current iteration if external condition is triggered. The current iteration of the loop is disrupted but program will return to the top of the loop.

This statement is written within the block after the if condition.

Syntax:

                        continue

Example:

A=0

while A<10:

    print(" A=", A)

    A=A+1

    if A>5:

        continue

        print("A=", A)

        print("Out of Loop")

O/P:

A=1

A=2

A=3

A=4

A=5

Out of Loop


3.         Pass Statement:

Pass statement in python used with loops when an external condition is triggered. Pass allows to handle this external trigger without the loop being impacted. All the code will be continue to read unless a break or other statements are occurs.

This statement is also written like other statements within the code block under the loop and after the if condition.

    Syntax:

            pass

Example:

A=0

while A<10:

    print(" A=", A)

    A=A+1

    if A>5:

        pass

        print("A=",A)

        print("Out of Loop")

O/P:

A=1

A=2

A=3

A=4

A=5

A=6

A=7

A=8

A=9

A=10

Out of Loop

 

4.         else statement in Loop:

In Python we can else statement in loops. 

When we use else statement in for loop the else loop is only executed when loop exhausted iteration of the list.

And when we use else statement in while loop the else statement is executed when condition becomes false.

Syntax:

            else:

Example:

for i in range(1,5):


  print(i)

else:

    print("No break")

O/P:

1

2

3

4

No break

 

The statement will execute because no break is there.

 

 Another Example: 

for i in range(1,5):

  print(i)

  break

else:

    print("No break")

 

O/P:

1

Only 1 will be displayed because condition  becomes true and flow of control will break with the help of break statement.

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