Count Alphabets Digits and Symbols in a String

Code

#include <stdio.h>
#include <stdint.h>
#define lim(x,min,max) (x>=min) && (x<max+1)
#define isAlpha(x) lim(x,65,90) || lim(x,97,122)
#define isDigi(x) lim(x,48,57)
#define isSymbol(x) lim(x,0,31) || lim(x,33,47) || lim(x,58,64) || lim(x,91,96) || lim(x,123,127)
void classify_chars(const char *str, uint8_t *alpha, uint8_t *digit, uint8_t *symbol) {
    // Your logic here
    *alpha = 0 ; 
    *digit = 0 ; 
    *symbol = 0 ;  

    while(*str)
    {
        *alpha += isAlpha(*str);
        *digit += isDigi(*str); 
        *symbol += isSymbol(*str);
        str+=1;
    }
}

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++;
    }

    uint8_t alpha = 0, digit = 0, symbol = 0;
    classify_chars(str, &alpha, &digit, &symbol);
    printf("Alphabets = %u\nDigits = %u\nSymbols = %u", alpha, digit, symbol);
    return 0;
}

Solving Approach