codewars

1.

function likes(names) {
 
  if(names.length===0){
    return "no one likes this";
  }
  if(names.length ===1){
    return names[0] + " likes this"
  }else if(names.length ===2){
    return names[0] +" and " +names[1] + " like this";
  }else if(names.length ===3){
    return names[0] +", "+ names[1] +" and " +names[2] + " like this";
  }else{
     return names[0] +", "+ names[1] +" and " +(names.length-2) +" others"+ " like this"; 
  }
}

2.

function findnb(m) {
  // 역으로 생각해서 1³ + (n-1)³+(n-2)³+...+n³이런식으로 생각하면 편함.
  let n = 1;
  let total = 0;
  while (total < m) {
    total += Math.pow(n, 3);
    if (total === m) {
      return n;
    }
    n++;
  }
  return -1;
}