Loops

While loop

Do-While Loops

It is similar to the while loop but with one key difference: the do-while loop always executes its body at least once, even if the condition is initially false.

Understanding how while and do-while loops can be simulated in place of each other by rearranging the code structure. :

Example:

int i = 0;
while (i < 10) {
    // Code to be executed
    i++;
}

This can be done using a Do-While loop as:

int i = 0;
do {
    // Code to be executed
    i++;
} while (i < 10);

The While loop checks the condition before executing the code, whereas, the Do-While loop executes the code first and then checks the condition. The examples above demonstrate how to rearrange the code to achieve the same functionality using either loop construct.

For loop

The for loop is suitable for situations where the number of iterations is known beforehand and depends on a counter variable.

Any or all of the initialization, condition, and update statements can be omitted, but the semicolons must still be present.

for (initialization; condition; update) {
    // code to be executed
}

#include <stdio.h>

int main() {
    int n, i;
    for (int n = 1; n < 10; n += 3)
    {
        for(int i = 1; i < 11; i++)
        {
            printf("%d*%d=%d\t%d*%d=%d\t%d*%d=%d\n",
                n,i,n*i,
                (n+1),i,(n+1)*i,
                (n+2),i,(n+2)*i);
        }
        printf("\n");
    }
    return 0;
}