四个数排序

#include<iostream>
using namespace std;
int main()
{int t,a,b,c,d;
cout<<"enter four numbers:";
cin>>a>>b>>c>>d;
cout<<"a="<<a<<"b="<<b<<"c="<<c<<"d="<<d<<endl;
if(a>b)
{t=a;a=b;b=t;}
if(a>c)
{t=a;a=c;c=t;}
if(a>d)
{t=a;a=d;d=t;}
if(b>c)
{t=b;b=c;c=t;}
if(b>d)
{t=b;b=d;d=t;}
if(c>d)
{t=c;c=d;d=t;}
cout<<"the sorted sequence:"<<endl;
cout<<a<<","<<b<<","<<c<<","<<d<<endl;
return 0;
}