C Do-While Loop

🔁 C Do-While Loop – Run First, Then Check

The do-while loop in C is like a while loop, but with a twist — it always runs the block at least once before checking the condition. Perfect for menus or input loops where you want something to happen first!

🔹 Syntax of do-while loop

do {
    // code to execute
} while (condition);

📝 Example: Count from 1 to 5

This program prints numbers from 1 to 5 using a do-while loop.

#include <stdio.h>

int main() {
    int i = 1;

    do {
        printf("Number: %d\n", i);
        i++;
    } while (i <= 5);

    return 0;
}
  

📝 Example: Run at Least Once (Even if Condition is False)

This shows that the loop runs even when the condition is false from the start.

#include <stdio.h>

int main() {
    int i = 10;

    do {
        printf("This runs at least once!\n");
    } while (i < 5);

    return 0;
}
  

🎯 Key Notes

• The block runs once before the condition is checked.
• Good for cases where you want to take input, display a menu, or run a message at least once.
• Always ends with a semicolon ; after the while() condition.

🎉 Practice Time!

Try modifying the condition or combining it with user input. Build a fun loop that asks for a password until it's correct!