()

true

()[]{}

true

(]

false

([])

true

class Solution:
    def isValid(self, s: str) -> bool:
        # 创建栈
        stack = []
        # 括号匹配字典
        brackets = {')': '(', ']': '[', '}': '{'}
        
        # 遍历字符串
        for char in s:
            # 如果是左括号，入栈
            if char in '([{':
                stack.append(char)
            # 如果是右括号
            elif char in ')]}':
                # 栈为空或栈顶不匹配，返回False
                if not stack or stack.pop() != brackets[char]:
                    return False
        
        # 检查栈是否为空
        return len(stack) == 0

# ACM模式输入输出
if __name__ == "__main__":
    solution = Solution()
    # 读取输入
    s = input().strip()
    # 输出结果
    print(solution.isValid(s))

import java.util.Scanner;

public class Main {
    public class Solution {
        public boolean isValid(String s) {
            // 创建字符数组作为栈
            char[] stack = new char[s.length()];
            int top = -1;  // 栈顶指针
            
            // 遍历字符串
            for (char c : s.toCharArray()) {
                // 如果是左括号，入栈
                if (c == '(' || c == '[' || c == '{') {
                    stack[++top] = c;
                } 
                // 如果是右括号
                else {
                    // 栈为空或不匹配，返回false
                    if (top == -1) return false;
                    char last = stack[top--];
                    if ((c == ')' && last != '(') || 
                        (c == ']' && last != '[') || 
                        (c == '}' && last != '{')) {
                        return false;
                    }
                }
            }
            
            // 检查栈是否为空
            return top == -1;
        }
    }

    public static void main(String[] args) {
        Main main = new Main();
        Solution solution = main.new Solution();
        // ACM模式输入
        Scanner sc = new Scanner(System.in);
        String s = sc.nextLine().trim();
        // 输出结果
        System.out.println(solution.isValid(s) ? "true" : "false");
        sc.close();
    }
}

#include <string>
#include <stack>
#include <iostream>
using namespace std;
class Solution {
public:
    bool isValid(string s) {
        // 创建栈
        stack<char> stack;
        
        // 遍历字符串
        for (char c : s) {
            // 如果是左括号，入栈
            if (c == '(' || c == '[' || c == '{') {
                stack.push(c);
            } 
            // 如果是右括号
            else {
                // 栈为空，返回false
                if (stack.empty()) return false;
                // 检查是否匹配
                char top = stack.top();
                stack.pop();
                if ((c == ')' && top != '(') || 
                    (c == ']' && top != '[') || 
                    (c == '}' && top != '{')) {
                    return false;
                }
            }
        }
        
        // 检查栈是否为空
        return stack.empty();
    }
};

// ACM模式输入输出
int main() {
    Solution solution;
    // 读取输入
    string s;
    getline(cin, s);
    // 输出结果
    cout << (solution.isValid(s) ? "true" : "false") << endl;
    return 0;
}