37 lines
906 B
C++
37 lines
906 B
C++
#include <iostream>
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#include "functions.h"
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using namespace std;
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int main()
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{
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// general
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int* pNumber = nullptr; // pointer definition, always initialize a pointer (at least with nullptr)
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pNumber = new int(0); // creates a new integer value on the heap
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cout << "size of pointer: " << sizeof(pNumber) << endl;
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cout << "size of pointer data: " << sizeof(*pNumber) << endl;
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*pNumber = 789;
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//pNumber = new int(0); // BAD BAD - memory leak, because we override an existin g pointer address with a new one without saving or deleting the old one
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// here are 100s lines of code
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if (pNumber != nullptr)
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{
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delete pNumber;
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pNumber = nullptr;
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}
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// pointer as references outside local scope
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int number = 10;
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changeInteger(number);
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number = changeIntegerPerReturn(number);
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changeIntegerPerPointer(&number);
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changeIntegerPerPointer(pNumber);
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changeIntegerPerReference(number);
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return 0;
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} |