#include<iostream>
#include<vector>
#include<string>
#include<cstdio>
#include<cctype>
using namespace std;
void print(vector<string> &);
void transform(vector<string>&,vector<string>&);
int main()
{
cout<<"请输入阿拉伯数字\n";
vector<string> _in_vec;
char tmp;
string s;
stringstream stream;
while((tmp = getchar()) != ‘\n‘)
{
if(tmp == ‘+‘||tmp==‘-‘||tmp==‘*‘||tmp==‘/‘||tmp==‘(‘||tmp==‘)‘)
{
if(!s.empty())
{
_in_vec.push_back(s);
s.clear();
}
stream<<tmp;
stream>>s;
stream.clear();
_in_vec.push_back(s);
s.clear();
}
else if(tmp == ‘ ‘)
{
if(!s.empty())
{
_in_vec.push_back(s);
s.clear();
}
}
else if(isdigit(tmp))
{
s += tmp;
}
}
if(!s.empty())
{
_in_vec.push_back(s);
s.clear();
}
print(_in_vec);
vector<string> _out_vec;
transform(_in_vec,_out_vec);
print(_out_vec);
return 0;
}
void print(vector<string> & _vec)
{
cout<<"\n";
for(int i = 0 ;i < _vec.size();i++)
cout<<_vec[i];
}
void transform(vector<string>&_in_vec,vector<string>&_out_vec)
{
vector<string> tmp;
for(int i = 0;i != _in_vec.size();i++)
{
if(isdigit((_in_vec[i]).at(0)))
_out_vec.push_back(_in_vec[i]);
else if(_in_vec[i] == ")")
{
while(!tmp.empty() && tmp.back() != "(")
{
_out_vec.push_back(tmp.back());
tmp.pop_back();
}
if(!tmp.empty())
tmp.pop_back();
}
else if(_in_vec[i] == "+" || _in_vec[i] == "-")
{
if(!tmp.empty() && (tmp.back() == "*" || tmp.back() == "/"))
{
_out_vec.push_back(tmp.back());
tmp.pop_back();
}
if(!tmp.empty() && (tmp.back() == "+" || tmp.back() =="-"))
{
_out_vec.push_back(tmp.back());
tmp.pop_back();
}
tmp.push_back(_in_vec[i]);
}
else if(_in_vec[i] == "*" || _in_vec[i] == "/")
{
if(!tmp.empty() && (tmp.back() == "*" || tmp.back() == "/"))
{
_out_vec.push_back(tmp.back());
tmp.pop_back();
}
tmp.push_back(_in_vec[i]);
}
else
tmp.push_back(_in_vec[i]);
}
while(!tmp.empty())
{
_out_vec.push_back(tmp.back());
tmp.pop_back();
}
}