版权声明：本文为博主原创文章，未经博主允许不得转载。 https://blog.csdn.net/wx1458451310/article/details/88384945
code:
#include<iostream>
#include<stack>
#include<string>
using namespace std;
int main()
{
string s;
stack<int> mystack;
while(cin>>s)
{
string news = s;
int len = s.length();
for(int i=0;i<len;i++)
{
//判断输入的字符，进行相应的处理
if(s[i] == '(')
{
mystack.push(i);
news[i] = ' ';
}
else if(s[i] == ')')
{
if(mystack.empty() == true)
news[i] = '?';
else
{
mystack.pop();
news[i] = ' ';
}
}
else
news[i] = ' ';
}
//剩下的（ 无法匹配，进行处理
while(!mystack.empty())
{
news[mystack.top()] = '$';
mystack.pop();
}
cout<<s<<endl<<news<<endl;
}
return 0;
}