Check if the String Numeric or Alphabetic

Code

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

void classify_string(const char *str) {
    // Your logic here
    int num_flag =0;
    int alpha_flag = 0;

    int i =0;
    while(str[i] != '\0'){
        if( str[i] <= '9' && str[i] >= '0'){
           // printf("NUMERIC");
           num_flag =1;
        }else if(str[i] <= 'Z' && str[i] >= 'A' || str[i] <= 'z' && str[i] >= 'a'){
           // printf("ALPHABETIC");
            alpha_flag = 1;
        }else{
            printf("MIXED");
            return;
        }
        i++;
    }
    if(num_flag && !alpha_flag){
        printf("NUMERIC");
    }else if(alpha_flag && !num_flag){
        printf("ALPHABETIC");
    }else{
        printf("MIXED");
    }
}

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