cpp 9.10

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9.10

#include<iostream>#include<new>const int BUF = 512;const int N = 5;char buffer[BUF];int main(){using namespace std;double *pd1, *pd2;int i;cout << "Calling new and placement new:\n";pd1 = new double[N];pd2 = new (buffer) double[N];for (i = 0; i < N; i++)pd2[i] = pd1[i] = 1000 + 20.0*i;cout << "Memory address:\n" << " heap: " << pd1<< " static: " << (void *)buffer << endl;cout << "Memory contents:\n";for (i = 0; i < N; i++){cout << pd1[i] << " at " << &pd1[i] << "; ";cout << pd2[i] << " at " << &pd2[i] << endl;}cout << "\nCalling new and placement new a second time:\n";double *pd3, *pd4;pd3 = new double[N];pd4 = new (buffer) double[N];for (i = 0; i < N; i++)pd4[i] = pd3[i] = 1000 + 40.0*i;cout << "Memory contents:\n";for (i = 0; i < N; i++){cout << pd3[i] << " at " << &pd3[i] << "; ";cout << pd4[i] << " at " << &pd4[i] << endl;}cout << "\nCalling new and placement new a third time:\n";delete[] pd1;pd1 = new double[N];pd2 = new(buffer + N * sizeof(double)) double[N];for (i =0; i < N; i++)pd2[i] = pd1[i] = 1000 + 60.0*i;cout << "Memory contents:\n";for (i = 0; i < N; i++){cout << pd1[i] << " at " << &pd1[i] << "; ";cout << pd2[i] << " at " << &pd2[i] << endl;}delete[] pd1;delete[] pd3;system("pause");return 0;}

namesp.h

#include<string>namespace pers{struct Person{std::string fname;std::string lname;};void getPerson(Person &);void showPerson(const Person &);}namespace debts{using namespace pers;struct Debt{Person name;double amount;};void getDebt(Debt &);void showDebt(const Debt &);double sumDebts(const Debt ar[], int n);}

namesp.cpp

#include<iostream>#include"namesp.h"namespace pers{using std::cout;using std::cin;void getPerson(Person & rp){cout << "Enter first name: ";cin >> rp.fname;cout << "Enter last name: ";cin >> rp.lname;}void showPerson(const Person &rp){std::cout << rp.lname << ", " << rp.fname;}}namespace debts{void getDebt(Debt & rd){getPerson(rd.name);std::cout << "Enter debt: ";std::cin >> rd.amount;}void showDebt(const Debt & rd){showPerson(rd.name);std::cout << ": $" << rd.amount << std::endl;}double sumDebts(const Debt ar[], int n){double total = 0;for (int i = 0; i < n; i++)total += ar[i].amount;system("pause");return 0;}}

namessp.cpp

#include<iostream>#include"namesp.h"void other(void);void another(void);int main(void){using debts::Debt;using debts::showDebt;Debt golf = { {"Benny", "Goatsniff"}, 120.0 };showDebt(golf);other();another();system("pause");return 0;}void other(void){using std::cout;using std::endl;using namespace debts;Person dg = { "Doodles", "Glister" };showPerson(dg);cout << endl;Debt zippy[3];int i;for (i = 0; i < 3; i++)getDebt(zippy[i]);for (i = 0; i < 3; i++)showDebt(zippy[i]);cout << "Total debt: $" << sumDebts(zippy, 3) << endl;system("pause");return;}void another(void){using pers::Person;Person collector = { "Milo", "Rightshift" };pers::showPerson(collector);std::cout << std::endl;}

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