leetcode 20 简单括号匹配

栈的运用

class Solution {
public:
    bool isValid(string s) {
        stack<char>The_Stack;
     int i=0;
     The_Stack.push('#');
     while(i<s.size()) {
         if((s[i]==')'&&The_Stack.top()=='(')||(s[i]==']'&&The_Stack.top()=='[')||(s[i]=='}'&&The_Stack.top()=='{')) {
             i++;
             The_Stack.pop();
         }
         else  {
         The_Stack.push(s[i]);
         i++;
         }
     }
     if(The_Stack.top()=='#')
     return true;
     return false;
    }
};