Readability

#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <cs50.h>
#include <ctype.h>
#include <string.h>

int main(void)
{
    char *article = "";  // get plaintext from the user they would like to check. declaring char * here is telling main to expect a char type input & a its gonna be a pointer to an array of characters somewhere in memory (i dunno where tho remember how these work?)
    do
    {
        article = get_string("Start typing dawg: ");
    }
    while (strlen(article) == 0);

    int letter = 0;    //  declare counting variable to count number of letters in plaintext article & set its value to 0
    int word = 0;      //  declare counting variable to count number of words in plaintext article & set its value to 0
    int sentence = 0;  //  declare counting variable to count number of sentances in plaintext article & set its value to 0

    int n = strlen(article);  // calculate stringlengh of entire article and store this in variable n

    for (int i = 0; i < n; i++) // forloop to loop through every character in the user's plaintext article
    {
        // count the number of letters in article
        if (isalnum(article[i]))  // if the [i]th character being checked in the loop in the array of article is alphanumeric, add a count to the letters in the article
        {
            letter++;
        }
        // count the number of words in the article
        if (i < n - 1 && isspace(article[i]) && isalnum(article[i + 1]))  // if i is less than the stringlengh of the article (minus the null char on the end of the string -1) AND the character at the ith index is a space AND the character in the spot of the array after is alphanumeric ([i + 1]), add a word to the count
        {
            word++;
        }
          // count the number of sentances in the article
        if (i > 0 && (article[i] == '!' || article[i] == '.' || article[i] == '?') && isalnum(article[i - 1]))   // we start checking if i > 0 so we can start this check at the start of the plaintext. If the plaintext character at the index of the array being checked is a "!" "." or "?" AND the character in the index of the array is also alphanumeric BEFORE the index of the first special char [i] that was checked is being performed on [-1], add to the count of total sentences
        {
            sentence++;
        }
    }

    double grade = 0.0588 * (100 * letter / word) - 0.296 * (100 * sentence / word) - 15.8;  // calculate Coleman-Liau index. This is: grade = 0.0588 * (Letters per 100 words) - 0.296 * (Sentences per 100 words) - 15.8
    printf("Letters: %i\nWords: %i\nSentences: %i\n", letter, word, sentence);  // show me letter, word and sentence count to make sure they are correct
    printf("grade number %f: ", grade);  // show grade value that is spat out of coleman-liau index

    if (grade <= 1)  //  print result: Your reading score is
    {
        printf("u retarded.\n");
    }
    else if (grade < 16)
    {
        printf("grade %f\n", grade);
    }
    else
    {
        printf("Big brain niBBa.\n");
    }
}