Count Alphabets Digits and Symbols in a String

Code

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

void classify_chars(const char *str, uint8_t *alpha, uint8_t *digit, uint8_t *symbol) {
    do
    {
        if(*str>=48 &&*str<=58)
        {
            *digit+=1;
        }
        else if(*str>=65 &&*str<=90 || *str>=97 &&*str<=122)
        {
            *alpha+=1;
        }
        else if(*str!=' ')
        {
            *symbol+=1;
        }
    }while(*str++!='\0');
    *symbol-=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