#include <bits/stdc++.h>
using namespace std;
string s;
stack<char> sta;
int main()
{
cin>>s;
for(int i=0;i<s.size();i++)
{
if(s[i]=='('||s[i]=='[') sta.push(s[i]);
else if(s[i]==')'||s[i]==']')
{
if(!sta.empty())
{
char top = sta.top();
// 检查栈顶元素与当前右括号是否匹配
if((top == '(' && s[i] == ')') || (top == '[' && s[i] == ']'))
sta.pop();
}
else {cout<<"false"; return 0;}
}
else continue;
}
if(sta.empty()) cout<<"true";
else cout<<"false";
return 0;
}



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