1. What does while (*str++); do?

• It checks if the character pointed to by str is not zero ('\0') and advances the pointer by one each time

• In short: it moves str forward until it reaches the end of the string

2. How does it work?

• *str++ means: First, use the value pointed to by str (the current character)

• Then increment str to point to the next character

• The loop continues until it encounters the null terminator '\0', where the condition becomes false

3. Is while (*str++); different from while (*str++ != '\0');?

• Functionally, both achieve the same result

• while (*str++); relies on the fact that the condition is false (zero) when it encounters '\0'

• while (*str++ != '\0'); makes the check explicit, but is slightly more verbose

Example demonstration:

#include <stdio.h>

int main() {
    char str[] = "hello";
    char *p = str;
    
    while (*p++)
        printf("Moving over: %c\n", *(p - 1));

    printf("Reached the end of string.\n");
    return 0;
}