Python Nested Loops

September 15, 2023

Nested Loop

A nested loop is a loop inside another loop. The “inner loop” will be executed one time for each iteration of the “outer loop”. If outer loop executes M times and inner loop executes N times , the time complexity of the loop will be (M*N). Nesting is, we can put any type of loop inside of any other type of loop. For example a for loop can be inside a while loop or vice versa

Nested Loop in Python

In Python, you can nest loops inside other loops to create more complex iterations. Nested loops involve one loop inside another, and the inner loop is executed for each iteration of the outer loop. This is commonly used for tasks like working with matrices, tables, or multi-dimensional data.

Syntax :

For/while (Outer Loop):
- For/while( Inner Loop) :
For/while ( Outer Loop) :
- if and else ( Inner Loop)r

Working :

The outer loop iterates through the range from 0 to n/len(sequence) and for each item in that sequence.
It enters the inner loop where it iterates over a range of that item.
For each iteration of that item, it perform the given operation.
It only leaves the inner loop when it has completely iterated through a range of that item.
When it leaves the inner loop, it goes back to the outer loop and the process continues until it has completely iterated over its sequence.

Example :

Run

#nested Loop
#for-for nested Loop 
for i in range(1,3):
    for j in range(1,6): #print the multiplication of 1 and 2 
        print(i*j,end=' ')
    print(' ')
#for-while nested loop
j=1
for i in range(1,3):
    j=1
    while(j<6):
        print(i*j, end =' ')
        j=j+1
    print(' ')
#while-while nested loop 
i=1
while(i<3):
    j=1
    while(j<6):
        print(i*j,end=' ')
        j=j+1
    print(' ')
    i+=1
#while-If nested Loop 
i=1
j=1
while(i<3):
    if(j<6):
        print(i*j, end =' ')
        j=j+1
    else:
        j=1
        i+=1
        print('')

If-else statement in Python

AND, OR and NOT in Python

Loops in Python

For Loops in Python

While Loop in Python

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