cos 1512 exam pack

JUNE 2017 P2

1 C STRINGS
Error Correction
If(str!=”STOP” If(strcmp(str,”STOP”);
Str = “STOP” Strcpy(str,”STOP”);



2 RECURSION
Void CountDown(int num)
{
If (num = 0)
Cout << 0 << endl;
Else
{
Cout << num << endl;
CountDown(num-1);
}
}


3 POINTERS

3.1 The problem with this this code fragment is that the code deletes the pointer.
Thereafter, the programmer is assigning the value to a pointer that doesn’t point to
anything. The results are disastrous.

3.2 Correct the Code

3.2.1 5 : p1 = &x; 6 : p2 = &y;
3.2.2 7: cout << *p1 << “ “ << *p2;
3.2.3 9: 30

3.3 typedef int* myPtr;
myPtr = a;
int size’;
a = new int[size];


4 DEFINE PRODUCT CLASS

Product.h

#ifndef PRODUCT_H
#define PRODUCT_H

#include <iostream>
#include <cstdlib>
#include <string>
#include <fstream>


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using namespace std;


class Product
{
public:
Product();
~Product();
long getNumber();
void reset(long rID, double rPrice, long rNum);
void increaseRetailPrice(float incPercent);
friend bool operator ==(const Product &p1, const Product &p2);
friend Product operator -- (Product &P);
friend istream& operator >> (istream& ins, Product &P);
friend ostream& operator << (ostream& outs, const Product &P);


protected:

private:
long id;
double price;
long number;
};

#endif // PRODUCT_H

Product.CPP
#include "Product.h"
#include <iostream>
#include <cstdlib>
#include <string>


using namespace std;

Product::Product()
{
id = 0;
price = 0.0;
number = 0;

}

Product::~Product()
{
//dtor
}

long Product::getNumber()

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{
return number;
}

void Product::reset(long rID, double rPrice, long rNum)
{
id = rID;
price = rPrice;
number = rNum;
}

void Product::increaseRetailPrice(float incPercent)
{
price = price + (price * incPercent);

}

bool operator ==(const Product &p1, const Product &p2)
{
if ((p1.id == p2.id) && (p1.price == p2.price) && (p1.number == p2.number))
return true;
else
return false;
}



Product operator-- (Product &P)
{

--P.number;

return P;


}

istream& operator >> (istream& ins, Product &P)
{
ins >> P.id >> P.price >> P.number;
//ins >> P.price;
//ins >> P.number;
return ins;
}

ostream& operator << (ostream& outs, const Product &P)
{
outs << P.id << endl;
outs << P.price << endl;
outs << P.number << endl;
return outs;

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}

Main()

#include <iostream>
#include <cstdlib>
#include <string>
#include <fstream>
#include "Product.h" //1


using namespace std;

int main()
{
ifstream input;//2
input.open("Products.txt");//3
if (input.fail())
{
cout << "File failed to open " ;
exit(1);
}
Product P1, P2;
long ID, Nr;
float Price;
cout <<"Enter product ID: ";
cin >> ID;
cout <<"Enter wholsesale Product price: ";
cin >> Price;
cout << "Enter number in stock of product" << "ID: ";
cin >> Nr;
P1.reset(ID,Price,Nr);//4
while(!input.eof()) // 5
{
input >> P2 ;//6
cout << P2.number; //6
}
if (P1 == P2) // 7
{
P2.increaseRetailPrice(0.05); //8
--P2; //9
}

cout << P1 << endl;
cout << P2 << endl;

input.close();

return 0;
}



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