Check if the String Numeric or Alphabetic

Code

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

void classify_string(const char *str) {
    int num = 0;
    int alpha =  0;
    int mixed = 0;

    while(*str){
        if(*str >= '0' && *str <= '9'){
            num = 1;
        }else if((*str >= 'a' && *str <= 'z') || (*str >= 'A' && *str <= 'Z')){
            alpha = 1;
        }else{
            mixed = 1;
        }

        str++;
    }

    if(mixed==1 || (num==1 && alpha==1)){
        printf("MIXED\n");
    }else if(num==1){
        printf("NUMERIC\n");
    }else{
        printf("ALPHABETIC\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