Remove Duplicate Characters from a String

Code

#include <stdio.h>
#include <stdint.h>

void remove_duplicates(char *str)
{
    int index = 0;

    for (int i = 0; str[i] != '\0'; i++)
    {
        int found = 0;

        for (int j = 0; j < index; j++)
        {
            if (str[i] == str[j])
            {
                found = 1;
                break; 
            }
        }

        if (!found)
        {
            str[index++] = str[i];
        }
    }

    str[index] = '\0';
}

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

    // Remove newline
    uint8_t i = 0;
    while (str[i])
    {
        if (str[i] == '\n')
        {
            str[i] = '\0';
            break;
        }
        i++;
    }

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

Solving Approach