第一次用VC编"河内塔"问题,编译之后无错,但是执行后非法操作,为什么呢?

[mimile]

#include "stdafx.h"


char * cPrint[64];
int iLine;

void make(int iA,int iB,int iC,int iS);
LRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM) ;
void ma()
{

make(1,2,3,10);
}


int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance,
PSTR szCmdLine, int iCmdShow)
{
static TCHAR szAppName[] = TEXT ("HelloWin") ;
HWND hwnd ;
MSG msg ;
WNDCLASS wndclass ;
wndclass.style = CS_HREDRAW | CS_VREDRAW ;
wndclass.lpfnWndProc = WndProc ;
wndclass.cbClsExtra = 0 ;
wndclass.cbWndExtra = 0 ;
wndclass.hInstance = hInstance ;
wndclass.hIcon = LoadIcon (NULL, IDI_APPLICATION) ;
wndclass.hCursor = LoadCursor (NULL, IDC_ARROW) ;
wndclass.hbrBackground = (HBRUSH) GetStockObject (WHITE_BRUSH) ;
wndclass.lpszMenuName = NULL ;
wndclass.lpszClassName = szAppName ;

if (!RegisterClass (&wndclass))
{
MessageBox (NULL, TEXT ("This program requires Windows NT!"),
szAppName, MB_ICONERROR) ;
return 0 ;
}

hwnd = CreateWindow (szAppName, // window class name
TEXT ("The Hello Program"), // window caption
WS_OVERLAPPEDWINDOW, // window style
CW_USEDEFAULT, // initial x position
CW_USEDEFAULT, // initial y position
CW_USEDEFAULT, // initial x size
CW_USEDEFAULT, // initial y size
NULL, // parent window handle
NULL, // window menu handle
hInstance, // program instance handle
NULL) ; // creation parameters

ShowWindow (hwnd, iCmdShow) ;
UpdateWindow (hwnd) ;

while (GetMessage (&msg, NULL, 0, 0))
{
TranslateMessage (&msg) ;
DispatchMessage (&msg) ;
}
return msg.wParam ;
}

LRESULT CALLBACK WndProc (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
HDC hdc ;
PAINTSTRUCT ps ;
RECT rect ;
int i;
switch (message)
{
case WM_CREATE:
ma();
return 0 ;

case WM_PAINT:
hdc = BeginPaint (hwnd, &ps) ;

GetClientRect (hwnd, &rect) ;

for (i=0;i<=iLine;i++)
{
TextOut(hdc,0,i*20,cPrint[i],lstrlen(cPrint[i]));
}

EndPaint (hwnd, &ps) ;
return 0 ;

case WM_DESTROY:
PostQuitMessage (0) ;
return 0 ;
}
return DefWindowProc (hwnd, message, wParam, lParam) ;
}









void make(int iA,int iB,int iC,int iS)

{

if (iS==0)
return;
make(iA,iC,iB,iS-1);

iLine++;

wsprintf(cPrint[iLine],"From %i to %i move the %i",iA,iC,iS);

make(iB,iA,iC,iS-1);



}

[Jim_Hu]

iLine有沒有越界

[jeffchen]

注意堆栈的大小是有限的，不能做太多次数的递归调用。有可能的话，用递推代替递归操作。

[kaitty]

有两个错误：
1。char * cPrint[64];这是申明了指针，并没有分配内存，做
wsprintf(cPrint[iLine],"From %i to %i move the %i",iA,iC,iS);
时是非法的。
2。当 iS = 10;时，iLine =1023;所以错作越界；
正确的代码如下：
#include "stdafx.h"


char* cPrint[1024];
int iLine;

void make(int iA,int iB,int iC,int iS);
LRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM) ;
void ma()
{
for(int i =0;i<1024;i++)
cPrint[i] = new char[30];
make(1,2,3,10);
}


int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance,
PSTR szCmdLine, int iCmdShow)
{
static TCHAR szAppName[] = TEXT ("HelloWin") ;
HWND hwnd ;
MSG msg ;
WNDCLASS wndclass ;
wndclass.style = CS_HREDRAW | CS_VREDRAW ;
wndclass.lpfnWndProc = WndProc ;
wndclass.cbClsExtra = 0 ;
wndclass.cbWndExtra = 0 ;
wndclass.hInstance = hInstance ;
wndclass.hIcon = LoadIcon (NULL, IDI_APPLICATION) ;
wndclass.hCursor = LoadCursor (NULL, IDC_ARROW) ;
wndclass.hbrBackground = (HBRUSH) GetStockObject (WHITE_BRUSH) ;
wndclass.lpszMenuName = NULL ;
wndclass.lpszClassName = szAppName ;

if (!RegisterClass (&wndclass))
{
MessageBox (NULL, TEXT ("This program requires Windows NT!"),
szAppName, MB_ICONERROR) ;
return 0 ;
}

hwnd = CreateWindow (szAppName, // window class name
TEXT ("The Hello Program"), // window caption
WS_OVERLAPPEDWINDOW, // window style
CW_USEDEFAULT, // initial x position
CW_USEDEFAULT, // initial y position
CW_USEDEFAULT, // initial x size
CW_USEDEFAULT, // initial y size
NULL, // parent window handle
NULL, // window menu handle
hInstance, // program instance handle
NULL) ; // creation parameters

ShowWindow (hwnd, iCmdShow) ;
UpdateWindow (hwnd) ;

while (GetMessage (&msg, NULL, 0, 0))
{
TranslateMessage (&msg) ;
DispatchMessage (&msg) ;
}
return msg.wParam ;
}

LRESULT CALLBACK WndProc (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
HDC hdc ;
PAINTSTRUCT ps ;
RECT rect ;
int i;
switch (message)
{
case WM_CREATE:
ma();
return 0 ;

case WM_PAINT:
hdc = BeginPaint (hwnd, &ps) ;

GetClientRect (hwnd, &rect) ;

for (i=0;i<iLine;i++)
{
TextOut(hdc,0,i*20,cPrint[i],lstrlen(cPrint[i]));
}

EndPaint (hwnd, &ps) ;
return 0 ;

case WM_DESTROY:
PostQuitMessage (0) ;
return 0 ;
}
return DefWindowProc (hwnd, message, wParam, lParam) ;
}

void make(int iA,int iB,int iC,int iS)

{

if (iS==0)
return;
make(iA,iC,iB,iS-1);

iLine++;

wsprintf(cPrint[iLine],"From %i to %i move the %i",iA,iC,iS);

make(iB,iA,iC,iS-1);



}

[ygd]

代码写错，栈益处

[mimile]

谢谢各位前辈