break & continue in python are used to control the flow of execution within loops. Both statements are used to alter the normal flow of a loop, but they are used in different situations. In this blog post, we will take a look at the break and continue statements, and when to use them in your Python code.
The break statement is used to exit a loop prematurely. When the break statement is encountered, the loop is immediately terminated, and the program continues to execute the next line of code after the loop. This can be useful when you have a specific condition that, when met, requires you to exit the loop. For example, consider the following code:
i = 0 while i < 10: i += 1 if i == 5: break print(i)
In this code, the break statement is encountered when the value of i is 5, which causes the loop to exit. As a result, the numbers 1 through 4 are printed, but the number 5 is not.
The continue statement, on the other hand, is used to skip over a single iteration of a loop. When the continue statement is encountered, the program immediately goes to the next iteration of the loop, without executing any of the remaining code in the current iteration. For example, the following code will only print the odd numbers in a list:
my_list = [1, 2, 3, 4, 5] for item in my_list: if item % 2 == 0: continue print(item)
In this code, the continue statement is encountered when the item in the list is even, which causes the program to skip over that iteration and move on to the next one. As a result, only the odd numbers in the list are printed.
It’s important to note that the break and continue statements can be used in both while and for loops, and also in nested loops. When using the break and continue statements in nested loops, it is important to pay attention to the level of indentation, as this will determine which loop the statement applies to.
Additionally, when using break statement in a nested loop, it will only break the innermost loop and not all the nested loops. For example, consider the following code:
for i in range(1,3): for j in range(1,3): if i == 2 and j == 2: break print(i,j)
In this code, the break statement is encountered when the value of i is 2 and j is 2, which causes the program to exit the innermost loop and not the outer one. As a result, the output will be 1 1, 1 2, 2 1
When using continue statement, it is important to be careful not to create an infinite loop by accidentally creating a situation where the loop never meets the break statement or the condition to exit the loop.
Another important point is, it’s always a good practice to use break and continue statements sparingly and only when they are truly necessary. Using them excessively can make your code harder to read and understand.
In conclusion, the break and continue statements in Python provide a way to control the flow of execution within loops.