Reverse a String In-Place

Code

#include <stdio.h>

void reverse_string(char *str)
{
   int start=0;
   int end=0;
   while(str[end]!='\0')
   {
    end++;
   }
   end--;

   while(start<end)
   {
    char temp=str[start];
    str[start] = str[end];
    str[end]=temp;
    start++;
    end--;
   }
}

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