프로그래머스 | 괄호변환

function solution(p) {
    var answer = '';
    if(p.length===0){ //재귀함수로 쓰기 때문에 빈문장일 경우를 잘 처리 해줘야 한다
        return answer;
    }else{
        let left='';
        let right='';
        let open=0;
        let close=0;
        for(let i=0;i<p.length;i++){
            if(p.charAt(i)==='('){
                open++;
            }else{
                close++
            }
            if(open===close){
                left=p.substring(0,open*2);
                right=p.substring(open*2,p.length)    
                break;
            }
        }
        if(isRight(left)){
            answer=left+solution(right);
        }else{
            answer+='(';
            answer+=solution(right)+')';
            left=left.substring(1,left.length-1);
            let LEFT='';
            for(let i=0;i<left.length;i++){
                if(left.charAt(i)==='('){
                    LEFT+=')'
                }else LEFT+='(';
            }
            answer+=LEFT;
        }
    }
     return answer;
}
function isRight(str){
    let arr=[];
    for(let i=0;i<str.length;i++){
        let e=str.charAt(i);
        if(e==='('){
            arr.push(e)
        }else{
            if(arr.length===0||arr[arr.length-1]!=='(') return false
            else arr.pop();
        }
    }
    if(arr.length===0)return true;
    else return false;
}