1 #include <iostream>
 2 #include <stack>
 3 #include <cstdlib>
 4 #include <ctime>
 5 using namespace std;
 6
 7 void StackSort(stack<int>& s)
 8 {
 9     stack<int> tmp;
10     while(!s.empty()){
11         tmp.push(s.top());
12         s.pop();
13     }
14     while(!tmp.empty()){
15         if(s.empty()){s.push(tmp.top());tmp.pop();}
16         else{
17             int x=tmp.top();
18             tmp.pop();
19             if(x<=s.top())   s.push(x);
20             else{
21                 while(!s.empty()&&x>s.top()){
22                     tmp.push(s.top());
23                     s.pop();
24                 }
25                 s.push(x);
26             }
27         }
28     }
29 }
30
31 void display(stack<int> s)
32 { while (!s.empty()) cout<<s.top()<<endl,s.pop();
33   cout<<endl;
34 }
35 int main(int argc,char**argv)
36 { const int n{20};
37   srand((unsigned)time(0));
38   stack<int> s;
39   for (int i{0};i<n;i++) s.push(rand()%100);
40   cout<<"Before sorting:"<<endl<<endl;  display(s);
41   cout<<"After sorting:"<<endl; StackSort(s); display(s);
42   return 0;
43 }