C++primer 9.6节练习

练习9.52

#include<iostream>
#include<string>
#include<vector>
#include <stack>

using namespace std;

//本来是想实现一个计算功能的，可是对于字符串转数值计算方面实在无能为力，等学的多了再回来看看
int main()
{
    string str1{ "(1 + ((2 + 3) * 5))" };
    bool count = true;
    stack<char> str;
    string str2;
    for (string::size_type it = 0; it != str1.size(); ++it)
    {
        if (str1[it] == '(')
            count = true;
        if (str1[it] == ')')
            count = false;
        if (count)
            str.push(str1[it]);
        if (!count)
        {
            while (str.top() != '(')
            {
                str2 += str.top();
                str.pop();
            }
            str.pop();
            count = true;
        }
    }
    cout << str2 << endl;
    system("pause");
    return 0;
}