归并排序实现

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




void merge(int *a ,int low, int mid ,int high)
{
    stack<int>    s;
    int i=low,j=mid+1;
    while(i<=mid&&j<=high)
    {
        if(a[i]<a[j])
            s.push(a[i++]);
        else
            s.push(a[j++]);
    }

    while(i<=mid)
        s.push(a[i++]);

    while(j<=high)
        s.push(a[j++]);

    for(i=high;i>=low;i--)
    {
        a[i]=s.top();
        s.pop();
    }
}

void mergesort(int *a ,int low , int high)
{
    if(low>=high)
        return;
    int mid = (low+high)/2;
    mergesort(a,low,mid);
    mergesort(a,mid+1,high);
    merge(a,low,mid,high);
}


void main()
{
    int a[100];
    int i;
    for(i=0;i<100;i++)
        a[i]=rand()%10000;
    mergesort(a,0,99);
    for(i=0;i<100;i++)
        cout<<a[i]<<endl;
}