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/*
pointers in c++ by Kristoffe Brodeur
06-04-2010
*/
#include <iostream>
using namespace std;
int main()
{
int numberArr[4]={1,3,7,11};
//
for(int a=0;a<4;a++)
{
cout << "element[" << a << "](" << numberArr[a] << ")\n";
}
int *pointerEle=&numberArr[2];
cout << "numberArr element [2] is (" << *pointerEle << ")" << endl;
cout << "to point to the next array element, add 1 to the pointer [2+1](" << *(pointerEle+1) << ")" << endl;
cout << "if parenthesis aren't used *(pointerEle+1) but *pointerEle+1 is\n";
cout << "You get he VALUE of *pointerEle's location +1, which is (" << *pointerEle << ")+1=" << *pointerEle+1 << endl;
cout << "------------------\n";
//-----dynamic arrays, finding free memoryand allocating it for use
//make a pointer, type integer and zero it out
int *newMemoryArr=0;
//with that pointer make a new array of 100 possible integers and allocate memory for it
newMemoryArr=new int[100];
int varTest=newMemoryArr[5];
varTest=216;
cout << "after making a new array of integers, we can then define them\n"
<< "by using a variable pointing to the memory location\n"
<< "the variable varTest=" << varTest << "\n"
<< "and the array newMemoryArr is a series of pointers to memory. \n"
<< "newMemoryArr[5]=" << newMemoryArr << "\n";
//-----expanding an array:if we need 166 positions but only hae 100 in newMemoryArr, we should make a larger array
int largerAmt=166;
//make a pointer, type integer and zero it out
int *newLargerArr=0;
newLargerArr=new int[largerAmt];
//
for(int x=0;x<100;x++)
{
newLargerArr[x]=newMmoryArr[x];
}
//c++ can mass readjust all pointers in the old array to point to the new array of 0-99(100)
newMemoryArr=newLargerArr;
//-----delete the array if no longer needed, to free up memory for something else
//delete [all cases 0~inf] of array newMemoryArr;
delete [] newMemoryArr;
delete [] newLargerArr;
system("PAUSE");
return EXIT_SUCCESS;
}