Kuidas on loodud side 'in' märksõna ja kogumite vahel C keeles?

In the C language, there is no keyword in, as in Python or other languages, where it is used to check if an element belongs to a collection.

If we are talking about working with collections in the context of Android (Java/Kotlin), then in is an operator that checks whether an element is contained in a collection. In C, such a construct does not exist, and the membership check is performed manually.

For example, to check if an element is in an array in C, you need to write a loop:

#include <stdbool.h>

bool contains(int *arr, int size, int value) {
    for (int i = 0; i < size; i++) {
        if (arr[i] == value) {
            return true;
        }
    }
    return false;
}

Therefore, in C, there is no direct connection between the keyword in and collections, because the keyword in itself does not exist in the language. All operations with collections are implemented through loops and functions.