TIL

재미있었던 장난감(코플릿)

function browserStack(actions, start) {

if (typeof start !== 'string')
  return false;

let nextStack = [];
let prevStack = [];
let now = start;

for ( let i = 0 ; actions.length >= i ; i++ ){
  if (actions[i] === -1 && prevStack.length !== 0){
      let prevPage = prevStack.pop() 
          nextStack.push(now)
          now = prevPage
  }else if (actions[i] === 1 && prevStack.length !== 0){
      let nextPage = nextStack.pop() 
          prevStack.push(now)
          now = nextPage
  }else if (typeof actions[i] === 'string'){
          prevStack.push(now)
          now = actions[i]
          nextStack = []
  }
}
  return [prevStack, now, nextStack];

} 

1) now를 지역변수로 선언해야하는 이유는?
2) prevPage와 nextPage를 따로 선언해야하는 이유는?

function browserStack(actions, start) {
  const present = [];
  const next = [];
  const prev = [];

  if (typeof start !== 'string'){
    return false;
  }
  present[0] = start;
  for (let i = 0; i < actions.length; i++){
    if(typeof actions[i] == 'string'){
      prev.push(present[0]);
      present.pop();
      present.push(actions[i]);
      next.length = 0
    }
    if(actions[i] === -1 && prev.length != 0){
      next.push(present[0]);
      present.pop();
      present[0] = prev.pop();
    }
    if(actions[i] === 1 && next.length != 0){
      prev.push(present[0]);
      present.pop();
      present[0] = next.pop();
    }
  }const result = present[0];
  return [prev, result, next]
}

코드를 입력하세요

실력있는 페어분이 캐리하신 코플릿.
주말동안 파봐야겠다.


...어드벤스드도!