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import java.lang.*;
import java.util.*;
class Parentheses {
public static boolean isValid(String s) {
HashMap<Character, Character> map = new HashMap<Character, Character>();
map.put(')','(');
map.put(']','[');
map.put('}','{');
Stack<Character> stack = new Stack<Character>();
char[] arr = s.toCharArray();
stack.push(arr[0]);
for (int i = 1; i < arr.length; i++) {
if (arr[i] == '(' || arr[i] == '[' || arr[i] == '{')
stack.push(arr[i]);
else if (map.get(arr[i]) == stack.peek())
stack.pop();
}
return stack.isEmpty();
}
public static void main(String[] args) {
String s = ")(";
System.out.println(isValid(s));
}
}
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