高手帮看下这道题为什么不能输出

#include <iostream>
using namespace std;
void main()
{
int n;
int pData[]={1,-2,3,4,5,-7};
int p=sizeof(pData)/sizeof(pData[0]);
bool FindGreatestSumOfSubArray(int pData[],unsigned int p, int n);

cout<<n<<endl<<p<<endl;


}

bool FindGreatestSumOfSubArray
(
int *pData, // an array
unsigned int nLength, // the length of array
int &nGreatestSum // the greatest sum of all sub-arrays
)
{
// if the input is invalid, return false
if((pData == NULL) || (nLength == 0))
return false;

int nCurSum = nGreatestSum = 0;
for(unsigned int i = 0; i < nLength; ++i)
{
nCurSum += pData[i];

// if the current sum is negative, discard it
if(nCurSum < 0)
nCurSum = 0;

// if a greater sum is found, update the greatest sum
if(nCurSum > nGreatestSum)
nGreatestSum = nCurSum;

}


// if all data are negative, find the greatest element in the array
if(nGreatestSum == 0)
{
nGreatestSum = pData[0];
for(unsigned int i = 1; i < nLength; ++i)
{
if(pData[i] > nGreatestSum)
nGreatestSum = pData[i];
}
}

return true;
}