import java.util.*;
public class Solution {
static Stack<Character> stack = new Stack<>();
public static boolean isValid(String s) {
if (s.length() == 0) {
return false;
}
char[] chars = s.toCharArray();
for (char c : chars) {
if (c == '{' || c == '[' || c == '(') {
stack.push(c);
} else if (c == '}') {
if (!stack.isEmpty() && stack.peek() == '{') {
stack.pop();
} else {
return false;
}
} else if (c == ']') {
if (!stack.isEmpty() && stack.peek() == '[') {
stack.pop();
} else {
return false;
}
} else if (c == ')') {
if (!stack.isEmpty() && stack.peek() == '(') {
stack.pop();
} else {
return false;
}
}
}
if (!stack.isEmpty()) {
return false;
}
return true;
}
}