WriteProcessMemory() on keystroke?

#include <iostream>
#include <windows.h>

using namespace std;

DWORD proc_id;
HANDLE hProcess;

int main()

{
     void CALLBACK PollKeys (HWND hWnd,UINT uMsg,UINT idEvent,DWORD dwTime);
   {
      if (GetAsyncKeyState(VK_F4))    // if F12 is down or was down since the last call
      {
         int ammo();      // call the trainer engine
      }
   }


 void CALLBACK PollKeys (HWND hWnd,UINT uMsg,UINT idEvent,DWORD dwTime);
   {
      if (GetAsyncKeyState(VK_F5))    // if F12 is down or was down since the last call
      {
        int health();      // call the trainer engine
      }
   }

}





int ammo()
{
HWND hWnd = FindWindow(0, "Modern Warfare 2");
GetWindowThreadProcessId(hWnd, &proc_id);
hProcess = OpenProcess(PROCESS_ALL_ACCESS|PROCESS_VM_OPERATION|PROCESS_VM_READ|PROCESS_VM_WRITE|PROCESS_QUERY_INFORMATION, FALSE, proc_id);


BYTE Nop[] = {0x90, 0x90, 0x90, 0x90};
WriteProcessMemory(hProcess, (LPVOID*)(DWORD) (0x004C6E0D), &Nop, sizeof(Nop), NULL); //health 0048286b
}


int health()
{
HWND hWnd = FindWindow(0, "Modern Warfare 2");
GetWindowThreadProcessId(hWnd, &proc_id);
hProcess = OpenProcess(PROCESS_ALL_ACCESS|PROCESS_VM_OPERATION|PROCESS_VM_READ|PROCESS_VM_WRITE|PROCESS_QUERY_INFORMATION, FALSE, proc_id);

    
BYTE Nop2[] = {0x90, 0x90, 0x90, 0x90, 0x90};
WriteProcessMemory(hProcess, (LPVOID*)(DWORD) (0x0048286b), &Nop2, sizeof(Nop2), NULL);	
}