Loops in C

In C, Loops are fundamental constructs in programming that allow us to repeat a block of code multiple times.

In C programming, there are mainly three types of loops: "for", "while", and "do-while".

Each loop type has its own syntax and use cases.

For Loop in C:

The "for" loop is commonly used when we know the number of iterations in advance.

Syntax:

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

Example:

Iterating over the number value, in our case condition is `3`.

Example:

#include <stdio.h>

int main() {
    int i;
    for (i = 0; i < 3; i++) {
        printf("Iterating value: %d \n", i);
    }
    return 0;
}

Output:

Iterating value: 0 
Iterating value: 1 
Iterating value: 2

when we enter in the for loop `i` variable is initialized to 0 and it checks condition `0` is less than 3 and the condition becomes true, so it will print `Iterating value: 0`, in the `for` loop statement and we also update the `i` value as well using `i++`.

Now, the `i` variable value is 1, and `1` is less than 3 so it will print the `Iterating value: 1` and increment the value of the `i` variable by 1. now the `i` value is 2.

During the 3rd iteration, it checks condition `i` is less than 3 and currently `i` value is 2, so it will iterate again and print `Iterating value: 2` and increment the value of `i` variable by 1.

During the 4th iteration, it checks condition `i`. 3 is less than 3 so it becomes false and comes out from the for loop and will not print anything.

While Loop in C:

The "while" loop is used when the number of iterations is not known beforehand, and the loop continues as long as the condition is true.

Syntax:

while (condition) {
    // Code to be executed
}

Example:

#include <stdio.h>

int main() {
    int i = 0;
    while (i < 3) {
        printf("Iterating Value: %d ", i);
        i++;
    }
    return 0;
}

In While Loop, we need to initialize our condition value before entering into the loop. Currently `i` value is 0 and 0 is less than 3. so it will print `Iterating Value: 0` and inside the while loop we are updating the `i` value using the statement `i++`.

Similarly, it will do when the `i` value is 1 and update the `i` value to 2.

Now, the `i` value is 2, and the condition `2 < 3` becomes true, so it enters in the condition and prints `Iterating Value: 2` and it will also increase the `i` value by 1 and now the `i` value is 3.

During the 4th iteration, it checks condition `i`. 3 is less than 3 so it becomes false and comes out from the while loop and will not print anything.

Do-While Loop in C:

The "do-while" loop is similar to the "while" loop, but it guarantees that the code block executes at least once before checking the condition.

Syntax:

do {
    // Code to be executed
} while (condition);

Example:

#include <stdio.h>

int main() {
    int i = 0;
    do {
        printf("%d ", i);
        i++;
    } while (i < 3);
    return 0;
}

Note:

Each type of loop has its own strengths and use cases.

It's essential to choose the appropriate loop based on the specific requirements of your program.

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