Remove Duplicate Characters from a String

Code

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

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

    for (int i = 0; i < len; 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];
            index++;
        }
    }

    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