Const modifier in C

main.c

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main(int argc, char* argv[]) {
    int n = 50, m = 60;
    
    const int * number_of_elements = &n;
    number_of_elements = &m; // valid
    *number_of_elements = 15; // invalid - will give compile error
    
    int * const number_of_elements2 = &n;
    number_of_elements2 = &m; // invalid - will give compile error
    *number_of_elements2 = 15; // valid
    
    return 0;
}