Loops.md

Python supports two main types of loops: for loops and while loops. I'll provide explanations, examples, outputs, characteristics, and definitions for both types of loops.

for Loops:

1. Definition: A for loop is used to iterate over a sequence (such as a list, tuple, string, or range) and execute a block of code for each element in the sequence.

2. Example:

   fruits = ["apple", "banana", "cherry"]
   
   for fruit in fruits:
   
       print(fruit)

3. Output:

   apple
   
   banana
   
   cherry
   

4. Characteristics:

   • for loops are used when you know the number of iterations in advance.

   • They automatically iterate through each element in the sequence.

while Loops:

1. Definition: A while loop repeatedly executes a block of code as long as a specified condition is True.

2. Example:

   count = 0
   
   while count < 5:
   
       print(count)
   
       count += 1

3. Output:

   0
   1
   2
   3
   4
   

4. Characteristics:

   • while loops are used when you don't know the number of iterations in advance.

   • They continue executing as long as the given condition remains True.

   • Be careful to ensure the loop condition eventually becomes False to prevent infinite loops.

Loop Control Statements:

1. break: Terminates the loop prematurely, even if the loop condition is still satisfied.

   for num in range(5):
   
       if num == 3:
   
           break
   
       print(num)

2. continue: Skips the current iteration and moves to the next iteration of the loop.

   for num in range(5):
   
       if num == 3:
   
           continue
   
       print(num)

Nested Loops:

You can have loops within loops (nested loops) to perform more complex operations. Just be cautious about the complexity and performance implications.

Loop Definitions:

1. for Loop Definition: A for loop is a control structure that iterates over a sequence of items and executes a block of code for each item in the sequence.

2. while Loop Definition: A while loop is a control structure that repeatedly executes a block of code as long as a specified condition is satisfied.

Loop Example with Nested for and while Loops:

for i in range(3):

    print(f"Outer loop iteration {i}")

    j = 0

    while j < 2:

        print(f"  Inner loop iteration {j}")

        j += 1

Output:

Outer loop iteration 0

  Inner loop iteration 0

  Inner loop iteration 1

Outer loop iteration 1

  Inner loop iteration 0

  Inner loop iteration 1

Outer loop iteration 2

  Inner loop iteration 0

  Inner loop iteration 1

In summary, loops are powerful tools for automating repetitive tasks in programming. Use for loops when you know the number of iterations, and while loops when you don't. Be cautious with loop control statements and nested loops to ensure your code is efficient and produces the desired results.