Readability

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

int main(void){
    string s = get_string("Text: ");
    int cletra = 0, cpalavra = 1, cfrase = 0;
    float L, S, x;

    //conta o total de letras
    for(int i=0, n=strlen(s); i<n; i++){
        if((s[i] >= 'a' && s[i] <= 'z') || (s[i] >= 'A' && s[i] <= 'Z')){
            cletra++;
        }
    }

    //conta o total de palavras
    for(int i=0, n=strlen(s); i<n; i++){
        if(s[i] == ' '){
            cpalavra++;
        }
    }

    //conta o total de frases
    for(int j=0, n=strlen(s); j<n; j++){
        if((s[j] == '.') || (s[j] == '!') || (s[j] == '?')){
            cfrase++;
        }
    }

    L = ((float) cletra/ (float) cpalavra)*100;
    S = ((float) cfrase/ (float) cpalavra)*100;

    x = 0.0588 * (100 * (float) cletra / (float) cpalavra) - 0.296 * (100 * (float) cfrase / (float) cpalavra) - 15.8;

    if(x>=16){
        printf("Grade 16+\n");
    }else{
        printf("Grade %i\n", (int) round(x));
    }
}