readability.c

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

int count_letters(string s);
int count_words(string s);
int count_sentences(string s);

int main(void)
{
    string text=get_string("Text: ");
    int letters = count_letters(text);
    printf("%i letter(s)\n", letters);
    int words = count_words(text);
    printf("%i word(s)\n", words);
    int sentences = count_sentences(text);
    printf("%i sentence(s)\n", sentences);
    //make sure the same type otherwise it will be not precise; float make sure everywhere is float.
    float L = (float)letters*100/(float)words;
    float S = (float)sentences*100/(float)words;
    float index = 0.0588*L-0.296*S-15.8;
    int index1 = (int)(index+0.5);
    if(index>=16)
    {
        printf("Grade 16+");
    }
    if(index<1)
    {
        printf("Before Grade 1");
    }
    if(index>=1&&index<16)
    {
        printf("Grade %i", index1);
        
    }
    printf("\n");
}

int count_letters(string s)
{
    int sum=0;
    for(int i=0,n=strlen(s);i<n;i++)
    {
        if((s[i]>='a'&&s[i]<='z')||(s[i]>='A'&&s[i]<='Z'))
        {
            sum++;
        }
    }
    return sum;
}

int count_words(string s)
{
    int sum=0;
    for(int i=0,n=strlen(s);i<n;i++)
    {
        if(s[i]==' ')
        {
            sum++;
        }
    }
    return sum+1;
}

int count_sentences(string s)
{
    int sum=0;
    for(int i=0,n=strlen(s);i<n;i++)
    {
        if(s[i]=='.'||s[i]=='!'||s[i]=='?')
        {
            sum++;
        }
    }
    return sum;
}