What is the basic idea to create a loop?

#1

what are the things we need to create a loop? how to decide that how many number of variables do we need to execute a loop? how to decide that which variable will go inside the loop for comparison? how to decide that which variable we need to put into the cout<< syntax??? please explain sir as i am not able to execute even a simple to print anything in loop program…please make sure to explain in hindi language.

#2

hi @Anku47
the variable you want to print depends on the usage. for eg you want to print counting from 1…n.
So you will need 2 variables, n to define the limit, and another variable to change its value. You will notice here that the value of n does not change. think of it logically like, you decided to print counting from 1 to 5, so when you have printed 1, 2, 3, you wont suddenly change n to 3, right? so n remains constant.
Now look at the structure of for loop here

int n = 5;
for (int i = 1; i <= n; i++) {
    cout << i << endl;
}

here you can see that, i is initialised with 1, therefore i = 1 when the loop starts. Then we increment i by 1 in each loop, and the condition is that i <= 5. so the loop will end when i reaches 6.

We can identify which variable to use by seeing which variable serves the purpose. For example, here we want to print counting from 1…n. so we need a variable that is changing its value regularly, n is not changing its value, it is a constant so we cannot use that. On the other hand, we made a loop specifically to change the value of i.
In this loop the value of i starts from 1 and goes till 5, so it will be perfect for this use case here.

I hope i have provided clarification to your doubt