[HELP] Windows has triggered a breakpoint ... VS2010... noob question, need help

#include “cuda_runtime.h”
#include “device_launch_parameters.h”
#include <stdio.h>
#include “Headers\book.h”
#include “Headers\stdafx.h”
using namespace std;
#define N 10
#define M 10

int main()
char UPAUSE;

int MaH[N*M], NaH[N*M];
int *NaD, *MaD;
int size = N*M;
HANDLE_ERROR( cudaMalloc( (void**)&MaD, N*M * sizeof(int)));
HANDLE_ERROR( cudaMalloc( (void**)&NaD, N*M * sizeof(int)));
for (int i=0; i < (M*N); i++)
	MaH[i] = i;
	NaH[i] = M*N-i;

for (int i=0; i<N*M; i++)
cout << MaH[i] << ", ";

for (int i=0; i<N*M; i++)
	   cout <<  NaH[i] << ", ";


HANDLE_ERROR( cudaMemcpy( MaD, MaH, size*sizeof (int), cudaMemcpyHostToDevice ) );
HANDLE_ERROR( cudaMemcpy( NaD, NaH, size*sizeof (int), cudaMemcpyHostToDevice ) );

cudaFree (MaD);
cudaFree (NaD);

    return 1;

i dont get why i keep getting the following messege?

Windows has triggered a breakpoint in Asg1.exe.

This may be due to a corruption of the heap, which indicates a bug in Asg1.exe or any of the DLLs it has loaded.

This may also be due to the user pressing F12 while Asg1.exe has focus.

The output window may have more diagnostic information.

Are you trying to free something you didn’t malloc?