Loops (for statements)

This lesson covers repeating logic in C using a for loop, so you can run the same code efficiently multiple times. It's for anyone searching "C for loop usage."

A for loop repeats the same logic. Instead of copying the same code across many lines, a loop lets you express a large amount of repetition in just a few lines.

The example uses for (int i = 1; i <= 5; i++) to print the numbers 1 through 5. This initialization/condition/update structure is the very syntax that countless other languages later modeled their own for loop on.

A common early mistake is confusing the roles of the three parts — initialization, condition, and update. Each one plays a distinct role: starting the loop, deciding whether to continue, and updating on each pass.

In real projects, this is an essential, everywhere-you-look construct — processing every element of an array one at a time, and much more.

📖 Reference code

#include <stdio.h>

int main(void) {
    for (int i = 1; i <= 5; i++) {
        printf("Loop pass %d\n", i);
    }
    return 0;
}

✍️ Your code

Type your code, then press "Run"

🧪 This site can't compile or run C directly, so it checks on the spot whether what you typed matches the reference code (scoring happens entirely in your browser — nothing is sent anywhere).