C ব্যবহার করে একটি বাক্যে স্পেস, আপারকেস এবং লোয়ারকেস গণনা

#include <stdio.h>
int main() {
    char str[100],i;
    int upper = 0, lower = 0, number = 0, special = 0,whitesp=0;
    printf("enter string");
    gets(str);
    for (i = 0; i < str[i]!='\0'; i++) {
        if (str[i] >= 'A' && str[i] <= 'Z')
            upper++;
        else if (str[i] >= 'a' && str[i] <= 'z')
            lower++;
        else if (str[i]>='0' && str[i]<='9')
            number++;
        else if(str[i]==' ')
            whitesp++;
        else
            special++;
    }
    printf("Upper case letters: %d\n",upper);
    printf("lower case letters: %d\n",lower);
    printf("Numbers: %d\n",number);
    printf("whitespace: %d\n",whitesp);
    printf("sp chararcter: %d\n",special);
    return 0;
}