Check if the String Numeric or Alphabetic

Code

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

void classify_string(const char *str) {
    bool numeric = false; 
    bool alphabetic = false;
    bool mixed = false;


    while(*str != 0){
        if((*str >= '0') && (*str <= '9')){
            numeric = true;
        }
        else if(((*str >= 'a') && (*str <= 'z')) || ((*str >= 'A') && (*str <= 'Z'))){
            alphabetic = true;
        }
        else{
            mixed = true;
        }       
        str++;
    }

    if(numeric && !alphabetic && !mixed){
        printf("NUMERIC\n");
    }
    else if(!numeric && alphabetic && !mixed){
        printf("ALPHABETIC\n");
    }
    else if((numeric && alphabetic) || mixed){
        printf("MIXED\n");
    }
}

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++;
    }

    classify_string(str);
    return 0;
}

Solving Approach