我的VC哪根筋搭错了？

[ntzls]

// DrawCos.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"
using namespace std;
int main(int argc, char* argv[])
{
cout<<"Hello World!\n";
return 0;
}
--------------------Configuration: DrawCos - Win32 Debug--------------------
Compiling...
DrawCos.cpp
C:\Program Files\Microsoft Visual Studio\MyProjects\DrawCos\DrawCos.cpp(5) : error C2871: 'std' : does not exist or is not a namespace
C:\Program Files\Microsoft Visual Studio\MyProjects\DrawCos\DrawCos.cpp(8) : error C2065: 'cout' : undeclared identifier
C:\Program Files\Microsoft Visual Studio\MyProjects\DrawCos\DrawCos.cpp(8) : error C2297: '<<' : illegal, right operand has type 'char [14]'
Error executing cl.exe.

DrawCos.exe - 3 error(s), 0 warning(s)
-----------------------------------------------------------
'std' : does not exist or is not a namespace？？？？？？？？？？？？？？？？？

[truewill]

#include <iostream>

[ntzls]

原来是我筋搭错了