Loops & Control Flow

🔵 C Programming Lesson 5 Beginner

Loops dictate iteration routines repeating blocks as long as a condition evaluates to true. C supports for, while, and do-while patterns.

1 Loop Structures & Iteration Steps

Choosing the correct loop construct improves code readability:

for: Best for static iteration sizes where initializers, conditions, and increments are grouped.
while: Best when the boundary conditions are checked before executing statement blocks.
do-while: Executes statement blocks first, and then verifies boundary conditions. Always executes at least one time.

2 Loop Control Tracing

Let's run a program printing iterations and checking flow behaviors with loop control actions:

C — Loops & break/continue ▶ Run Code

#include <stdio.h>

int main() {
    // For loop demonstration
    printf("For sequence: ");
    for (int i = 1; i <= 5; i++) {
        printf("%d ", i);
    }
    printf("\n");

    // While loop with loop control bypasses
    printf("While sequence (skipping 3, stopping at 7): ");
    int count = 1;
    while (count <= 10) {
        if (count == 3) {
            count++;
            continue; // Skip rest of block, check condition again
        }
        if (count == 7) {
            break; // Terminate loop block completely
        }
        printf("%d ", count);
        count++;
    }
    printf("\n");

    return 0;
}

3 Code Challenge

Challenge: Write a program that computes the factorial of an integer (e.g. `5` -> factorial = 5*4*3*2*1 = 120). Implement this computation using a `while` loop, and print the final result.