我在VC＋＋6.0运行，为什么有这么多错误啊

-------------------Configuration: Cpp124 - Win32 Debug--------------------
Compiling...
Cpp124.cpp
C:\Documents and Settings\time\My Documents\Cpp124.cpp(51) : error C2065: 'getch' : undeclared identifier
C:\Documents and Settings\time\My Documents\Cpp124.cpp(66) : warning C4508: 'main' : function should return a value; 'void' return type assumed
C:\Documents and Settings\time\My Documents\Cpp124.cpp(156) : error C2065: 'clrscr' : undeclared identifier
C:\Documents and Settings\time\My Documents\Cpp124.cpp(455) : warning C4129: 'd' : unrecognized character escape sequence
C:\Documents and Settings\time\My Documents\Cpp124.cpp(465) : warning C4129: 'd' : unrecognized character escape sequence
C:\Documents and Settings\time\My Documents\Cpp124.cpp(480) : warning C4129: 'd' : unrecognized character escape sequence
C:\Documents and Settings\time\My Documents\Cpp124.cpp(485) : warning C4129: 'd' : unrecognized character escape sequence
Error executing cl.exe.

Cpp124.obj - 2 error(s), 5 warning(s)

我测出来好象有bug,就是学号竟然可以重复，望改正一下。

楼主啊，有些错误的哦

:\Documents and Settings\Administrator\Cpp1.cpp(33) : error C2065: 'clrscr' : undeclared identifier
C:\Documents and Settings\Administrator\Cpp1.cpp(51) : error C2065: 'getch' : undeclared identifier
C:\Documents and Settings\Administrator\Cpp1.cpp(66) : warning C4508: 'main' : function should return a value; 'void' return type assumed
C:\Documents and Settings\Administrator\Cpp1.cpp(455) : warning C4129: 'd' : unrecognized character escape sequence
C:\Documents and Settings\Administrator\Cpp1.cpp(465) : warning C4129: 'd' : unrecognized character escape sequence
C:\Documents and Settings\Administrator\Cpp1.cpp(480) : warning C4129: 'd' : unrecognized character escape sequence
C:\Documents and Settings\Administrator\Cpp1.cpp(485) : warning C4129: 'd' : unrecognized character escape sequence
Error executing cl.exe.

Cpp1.obj - 2 error(s), 5 warning(s)

谢谢啊。