Remove Duplicate Characters from a String

Code

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

void remove_duplicates(char *str) {
	//Your logic here
     int seen[256] = {0};  
    int write_index = 0;

    for (int read_index = 0; str[read_index] != '\0'; read_index++) {
        unsigned char ch = str[read_index];
        if (!seen[ch]) {
            seen[ch] = 1;                 
            str[write_index++] = ch;      
        }
    }
    str[write_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