function convertCamelName(name) {
  let camelName = '';

  for (let i = 0, newSpace = false; i < name.length; i++) {
    if (name[i] == ' ') {
      newSpace = true;
      continue;
    }

    if (newSpace) {
      camelName = camelName + name[i].toUpperCase();
      newSpace = false;
    } else {
      camelName = camelName + name[i].toLowerCase();
    }
  }
  return camelName;
}

const camelName1 = convertCamelName('kim hee tae');
console.log(camelName1); // kimHeeTae

const simpleCamel = (input) => input.split(' ')
  .map((text, idx) => text.split('')
    .map((word, idxx) => idx > 0 && idxx == 0 ? word.toUpperCase() : word.toLowerCase())
    .join(''))
  .join('');

const camelName2 = simpleCamel('kim hee tae');
console.log(camelName2); // kimHeeTae