#include <stdio.h>

int main() {
    // While loop
    int counter = 0;
    while (counter < 5) {
        printf("Counter: %d\n", counter);
        counter++;
    }

    // For loop
    for (int i = 0; i < 5; i++) {
        printf("Index: %d\n", i);
    }

    // Do-while loop
    int x = 5;
    do {
        printf("Value of x: %d\n", x);
        x--;
    } while (x > 0);

    return 0;
}

Explanation:

1. #include <stdio.h>:

   • This line is a preprocessor directive, telling the compiler to include the standard input/output library (stdio.h), which provides functions like printf.

2. int main() { ... }:

   • This is the main function where the program execution starts. The { and } curly braces define the start and end of the main function.

While Loop:

// While loop
int counter = 0;
while (counter < 5) {
    printf("Counter: %d\n", counter);
    counter++;
}

• counter is initialized to 0.
• The while loop checks if counter is less than 5.
• Inside the loop:
  • It prints the current value of counter.
  • Increments counter by 1.
• The loop continues until counter is no longer less than 5.

For Loop:

// For loop
for (int i = 0; i < 5; i++) {
    printf("Index: %d\n", i);
}

• The for loop has three parts: initialization (int i = 0), condition (i < 5), and increment (i++).
• Inside the loop:
  • It prints the current value of i.
• The loop runs as long as the condition (i < 5) is true.

Do-While Loop:

// Do-while loop
int x = 5;
do {
    printf("Value of x: %d\n", x);
    x--;
} while (x > 0);

• x is initialized to 5.
• The do-while loop executes the block of code first and then checks the condition (x > 0).
• Inside the loop:
  • It prints the current value of x.
  • Decrements x by 1.
• The loop continues until the condition (x > 0) is false.

return 0;:

• Indicates that the program executed successfully. The 0 here is a convention for indicating a successful execution.

These loops are fundamental for controlling the flow of your program. The while loop continues as long as the specified condition is true, the for loop repeats a block of code a specified number of times, and the do-while loop ensures that the code is executed at least once before checking the condition.

How to Run

To run this program:

1. Make sure you have a C compiler installed on your computer.
2. Copy the code into a file with a .c extension, for example, loop.c.
3. Open a terminal or command prompt and navigate to the directory where your file is located.
4. Compile the program by entering: gcc loop.c -o loop
5. Run the compiled program: ./loop

Or you can run this program also using:

   make loop

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