How to calculate the highest order of a number x in C

In C programming, to find the highest order (i.e., the power of 10) that divides a given integer `x` without leaving any remainder, you can use the logarithm function or an iterative approach with division and modulo operations. Here's an example using both methods:

**Method 1: Using log10() function**

#include <math.h>

int highest_order(int x) {
    if (x <= 0) {
        return 0; // Return 0 for negative numbers and zero
    }
    int exponent = floor(log10(x)); // Floor function to get whole number part
    return exponent;
}

**Method 2: Iterative approach with division and modulo**

#include <stdio.h>

int highest_order(int x) {
    if (x <= 0) {
        return 0; // Return 0 for negative numbers and zero
    }

    int order = 0;
    while (x % 10 == 0) {
        x /= 10; // Divide by 10 each time
        order++;
    }
    return order;
}

Both functions will return the highest power of 10 that divides `x`.