Remove Duplicate Characters from a String

Code

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

void remove_duplicates(char *str) {
char dat[256]={0};
char *read = str;
char *write = str;
    while(*read){
        if(dat[(unsigned char)*read]==0){
            *write=*read;
            dat[(unsigned char)*read]=1;
            write++;
        }
        read++;
    }
    *write='\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