谁来帮我找找错啊int max(int a,int b);void main(){int x,y,z;int max(i

谁来帮我找找错啊
int max(int a,int b);
void main()
{
int x,y,z;
int max(int a,int b);
printf("input two numbers:\n");
scanf("%d%d","&x,&y");
z=max(x,y);
printf("maxmum=%d",z);
}
int max(int a,int b);
{
if(a>b) return a;else return b;
}
------------------Configuration:Max - Win32 Debug--------------------
Compiling...
比较大小.c
C:\Program Files\Microsoft Visual Studio\MyProjects\Max\比较大小.c(6) :warning C4013:'printf' undefined; assuming extern returning int
C:\Program Files\Microsoft Visual Studio\MyProjects\Max\比较大小.c(7) :warning C4013:'scanf' undefined; assuming extern returning int
C:\Program Files\Microsoft Visual Studio\MyProjects\Max\比较大小.c(14) :error C2449:found '{' at file scope (missing function header?)
C:\Program Files\Microsoft Visual Studio\MyProjects\Max\比较大小.c(16) :error C2059:syntax error :'}'
Error executing cl.exe.
比较大小.obj - 2 error(s),2 warning(s)