// Mr. Minich // CMPSC 101 // Ch. 7 Demo #9 // November 1, 2001 // Purpose - to illustrate the use of flag variables #include <iostream>using namespace std; int main() { int boughtApples = 0; // flag variable for apple purchase (0 is false) int boughtGrapes = 0; // flag variable for grape purchase (0 is false) int menuChoice = 0; // user's choice from menu int numApples = 0; // number of apples purchased by user double currentTotalSpent = 0.0; // total amount of money spent by user while (!boughtApples || !boughtGrapes || menuChoice != 3) { cout << endl; cout << "1 Apples" << endl; cout << "2 Grapes" << endl; cout << "3 Exit" << endl << endl; cout << "Enter your menu choice: "; // loop iterates until either the user has purchased both apples or grapes or the user exits cin >> menuChoice; if (menuChoice == 1) { if (!boughtApples) { cout << "Enter number of apples: "; cin >> numApples; if (numApples * .5 + currentTotalSpent <= 100) { currentTotalSpent += numApples * .5; // do something appropriate with a flag variable here } else { // do something here } } else { // do something here } } else if (menuChoice == 2) { // do stuff here } else if (menuChoice == 3) { break; // exiting loop since user chose to exit } } cout << endl << "You owe $" << boughtGrapes * 1.25 + boughtApples * 0.50 << endl; return 0; }// end of main