Brackets

Brackets

Determine whether a given string of parentheses (multiple types) is properly nested.

A string S consisting of N characters is considered to be properly nested if any of the following conditions is true:

S is empty;
S has the form "(U)" or "[U]" or "{U}" where U is a properly nested string;
S has the form "VW" where V and W are properly nested strings.
For example, the string "{[()()]}" is properly nested but "([)()]" is not.

Write a function:

function solution(S);

that, given a string S consisting of N characters, returns 1 if S is properly nested and 0 otherwise.

For example, given S = "{[()()]}", the function should return 1 and given S = "([)()]", the function should return 0, as explained above.

Write an efficient algorithm for the following assumptions:

N is an integer within the range [0..200,000];
string S consists only of the following characters: "(", "{", "[", "]", "}" and/or ")".
Copyright 2009–2019 by Codility Limited. All Rights Reserved. Unauthorized copying, publication or disclosure prohibited.

나의 풀이

문제 풀이 링크

function solution(S) {
    const nested = [];
    for (let i = 0; i < S.length; i++) {
        if (S[i] === '{' || S[i] === '[' || S[i] === '(') {
            nested.push(S[i]);
        } else if (
            (S[i] === '}' && nested[nested.length - 1] === '{') ||
            (S[i] === ']' && nested[nested.length - 1] === '[') ||
            (S[i] === ')' && nested[nested.length - 1] === '(')
        ) {
             nested.pop();
        } else {
            return 0;
        }
    }
    if (nested.length === 0) {
        return 1;
    } else {
        return 0;
    }
}