其实就是括号匹配,直接用java封装的stack类来解决:
import java.util.Stack;
class Solution {
public boolean isValid(String s) {
Stack<Character> stack = new Stack<Character>();
for(int i=0;i<s.length();i++) {
if(s.charAt(i)=='('||s.charAt(i)=='['||s.charAt(i)=='{') {
stack.push(s.charAt(i));
}
else if(!stack.empty()) {
char temp = stack.pop();
int dis = s.charAt(i)-temp;
if(dis!=1&&dis!=2)
return false;
}
else
return false;
}
if(!stack.empty()) return false;
return true;
}
}