Python – Break out from Nested Loops
To break out of all the loops from an inner loop in Python, set a boolean flag in inner loop before break out, and then check this flag in all the outer loops as a condition to break out from them as well.
The following is a simple pseudo code snippet depicting the use of the break flag to break out of all outer loops from an inner loop.
Pseudo Code
breakFlag = False
for i in x:
for j in y:
for k in z:
...
if some_condition_to_break_out_from_all_loops:
breakFlag = True
break
if breakFlag:
break
if breakFlag:
break
Example
In the following example, we will take a three level nested For Loop, and break out of all the loops form the inner most loop using a flag.
Python Program
breakFlag = False
for i in range(10):
for j in range(i):
for k in range(j):
if i == 4 and j == 2 and k == 2:
breakFlag = True
break
print('*', end='')
if breakFlag:
break
print(' ', end='')
if breakFlag:
break
print()
Run Code CopyOutput
*
* **
* ** ***
* ** *** ****
* ** *** **** *****
* ** *** **** ***** ******
* ** *** **** ***** ****** *******
* ** *** **** ***** ****** ******* ********
References
Summary
In this tutorial of Python Examples, we learned how to break out from all the loops from an inner loop using a boolean flag and break statement, with detailed examples.