Hello i m learning c++ ..so maybe this ll be very easy solution for you guys
 
#include<iostream.>
#include<conio.h>
void main()
{
int a,b,c;
clrscr();
cout<<"Enter Your 1st Value";
cin>>a;
cout<<"Enter Your 2nd value";
cin>>b;
cout<<"Enter your 3rd value";
cin>>c;
 
              if(a>b&&c)
                {
                    cout<<"1st value is greater";
                }
                           else if(b>a&&c)
                                {
                                          cout<<"2nd value is greater";
                                }
              else if(c>b&&a)
                     {
                           cout<<"3rd value is greater";
                     }
 
getch();
}