C While Loop
Loops
Loops can execute a block of code as long as a specified condition is reached.
Loops are handy because they save time, reduce errors, and they make code more readable.
While Loop
The while loop loops through a block of code as long as a specified condition is true:
Syntax
while (condition) {
// code block to be executed
}
In the example below, the code in the loop will run, over and over again, as long as
a variable (i) is less than 5:
Note: Do not forget to increase the variable used in the condition
(i++), otherwise
the loop will never end!
Do you wonder why we use the letter i as a variable name? It's a counter variable and a common choice in simple loops because it's short, traditional, and stands for 'index' or 'iterator'.
Countdown Example
This example counts down from 3 to 1 and then displays "Happy New Year!!" at the end:
Example
int countdown = 3;
while (countdown > 0) {
printf("%d\n", countdown);
countdown--;
}
printf("Happy New Year!!\n");
Try it Yourself »
