This is a solution for the 'Drawing book' problem by hackerrank. It was made in Javascript (Node js)

Hackerrank 'Drawing book'

function pageCount(n, p) {
    // Write your code here
    //Identificar desde que lado empezaremos
    let foundPage = false;
    let currentPages = 0;
    let counts = 0;
    let tipoDeNumero = 0;
    if(n%2!=0){
        //Numero par = 0
        //Numero impar = 1
        tipoDeNumero = 1;
    }
   
    if(p<=n/2){
        //left side
        currentPages = [0,1];
        counts = 0;
        while(!foundPage){
            //Buscamos en el arreglo si coincide p
            if(currentPages.includes(p)){
                foundPage = true;
                break;
            }
            //sumamos un count 
            counts++;
            //Actualizamos las paginas
            currentPages[0] = currentPages[0] + 2;
            currentPages[1] = currentPages[1]+2;
            
        }
    }
    else{
        //right side
         //Si el numero es par entonces el arreglo empieza en [n, n+1]
         if(tipoDeNumero==0)
         {
           currentPages = [n,n+1]  
         }
         else
         {
        currentPages = [n-1,n];
         }
        counts = 0;
        while(!foundPage){
            //Buscamos en el arreglo si coincide p
            if(currentPages.includes(p)){
                foundPage = true;
                break;
            }
            //sumamos un count 
            counts++;
            //Actualizamos las paginas
            currentPages[0] = currentPages[0] - 2;
            currentPages[1] = currentPages[1] - 2;
            
        }
    }
    return counts;
}