Check if the String Numeric or Alphabetic

Code

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

void classify_string(const char *str) 
{
    int i=0;
    char n_flag=0;
    char a_flag=0;

    while(str[i])
    {
        if(isdigit(str[i]))
         n_flag=1;
        else if(isalpha(str[i]))
         a_flag=1;
        else
        {
          printf("MIXED"); 
          return ;
        }

         i++;
    }


    if(n_flag && !a_flag) //actually a_flag=0 remains when we donot find any alphabet and n_flag=1 means we found numeric. When both are satisfied it tells that it is purely numeric.
      printf("NUMERIC");
    else if(a_flag && !n_flag) //same logic as above.
      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