A build problem in Qt creator 1

[Dante]

Hi pals
I just installed Qt on windows XP and to become familiar with the details of Qt creator c++ programming, I wrote this code:

#include "test.h"
#include <conio.h>
#include <iostream.h>
void main(){
    int x;
    cin>>x;
    cout<<x*x;
    getch();}

#include "test.h"
#include <conio.h>
#include <iostream.h>
void main(){
    int x;
    cin>>x;
    cout<<x*x;
    getch();}

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but when i clicked on build menu,all icons were disabled.I saved the file but there was still no answer.
and one more thing.
in Qt creator code editing page,there is a wavy line under the #include lines.
thanks