stack排序

Cracking Interview 3-6

用的书上的思路，O(n^2)的时间复杂度。

#include <iostream>
#include <stack>
using namespace std;

stack<int> sort(stack<int> unorderStack)
{
    stack<int> orderStack;
    stack<int> tmpStack;

    while(!unorderStack.empty())
    {
        int value = unorderStack.top();
        if (orderStack.empty())
            orderStack.push(value);
        else if (value < orderStack.top())
            orderStack.push(value);
        else {
            while (!orderStack.empty() && value > orderStack.top()){
                tmpStack.push(orderStack.top());
                orderStack.pop();
            }
            orderStack.push(value);
            while (!tmpStack.empty()){
                orderStack.push(tmpStack.top());
                tmpStack.pop();
            }
        }
        unorderStack.pop();
    }
    return orderStack;
}

int main()
{
    stack<int> stk;
    for (int i = 0; i < 10; i++)
    {
        int value = rand()%150;
        cout<<"Pushing : "<<value<<endl;
        stk.push(value);
    }
    cout<<"sorting ..."<<endl;
    stk = sort(stk);
    cout<<"sort complete"<<endl;
    while (!stk.empty())
    {
        cout<<stk.top()<<endl;
        stk.pop();
    }
    return 0;
}

EOF