Reverse a String In-Place

Code

#include <stdio.h>

void reverse_string(char *str) {
    // Your logic here
    int i = 0;
    int len = 0;
    while (str[len] != '\0') ++len;

    --len;
    while (i < len){
        char tmp = str[i];
        str[i] = str[len];
        str[len] = tmp;
        ++i; --len;
    }
}

int main() {
    char str[101];
    fgets(str, sizeof(str), stdin);

    // Remove newline
    int i = 0;
    while (str[i] != '\0') {
        if (str[i] == '\n') {
            str[i] = '\0';
            break;
        }
        i++;
    }

    reverse_string(str);
    printf("%s", str);
    return 0;
}

Solving Approach