对三个变量按由小到大的顺序排序

#include <iostream>

/* run this program using the console pauser or add your own getch, system("pause") or input loop */
using namespace std;
int main(int argc, char** argv) {
    void sort(int &,int &,int &);
    int a,b,c;
    int a1,b1,c1;
    cout <<"please enter 3 inteers:";
    cin >>a>>b>>c;
    a1=a;
    b1=b;
    c1=c;
    sort(a1,b1,c1);
    cout <<"sorted order is "<<a1<<" "<<b1<<" "<<c1<<endl;
    return 0;
}

void sort(int &i,int &j,int &k){
    void change(int &,int &);
    if(i>j) change(i,j);
    if(i>k) change(i,k);
    if(j>k) change(j,k);
}

void change(int &x,int &y)
{
    int temp;
    temp=x;
    x=y;
    y=temp;
}