防抖 节流

//防抖

const debounce = function(func, delay) {
  let timer = 0;
  return function() {
    clearTimeout(timer)
    timer = setTimeout(() => {
      func()
    }, delay)
  }
}

//节流

const throttle = function(func, delay) {
  let timer = +new Date();
  return function() {
    let cur = +new Date();
    if (cur - timer > delay){
      func(...arguments);
      timer = cur;
    }
  }
}