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#include

#include

#include

#include // file stream

#include // cin, cout

#include

#include // STL sort()

using namespace std;

char menu(); // show user chocies

void execute(const char command); // perform a user's choice

void create_data();

void load_data(char const *fn); // load data from fn

void display_data();

void save_data(char const *fn); // save data to file fn

void about();

// menu choices

const char ABOUT = '0'; // use

characters it is safer for input

const char CREATE_DATA = '1';

const char LOAD_DATA = '2';

const char DISPLAY_DATA = '3';

const char SHOW_DIRECTORY = '4';

const char SAVE_DATA = '5';

const char SORT_DATA = '6';

const char QUIT = 'Q';

const int N = 100;

int myData[N]; // can hold 10 data items

char const *filename = "myData.txt"; // default data file name

int main()

{

char command;

do {

command = menu();

execute(command);

system("pause");

} while (toupper(command) != QUIT);

return 0;

}

char menu(){

char c;

do {

system("cls");

cout << "command menu ";

cout << "0.....About ";

cout << "1.....Create Data ";

cout << "2.....Load Data ";

cout << "3.....Display ";

cout << "4.....Directory ";

cout << "5.....Save Data ";

cout << "6.....Sort Data ";

cout << "Q.....Quit ";

cout << "choice: ";

cin >> c;

} while ( !('0'<=c && c<='6') && c!='Q');

return c;

}

void execute(const char command) {

switch (toupper(command)) {

case ABOUT:

about();

break;

case CREATE_DATA:

create_data();

break;

case LOAD_DATA:

load_data(filename);

break;

case SAVE_DATA:

save_data(filename);

break;

case DISPLAY_DATA:

display_data();

break;

case SHOW_DIRECTORY:

system("dir /a/p *.txt "); // only show files ending with

txt

break;

case SORT_DATA:

sort(myData, myData + N); // STL using default ordering

break;

} // end of switch statement

} // end of execute function

void about()

{

cout << " SAMPLE of menu driven programming ";

cout << "(c) copyright 2011 your name. All rights reserved. ";

}

void create_data()

{

cout << "Generating data ";

srand( time(NULL) ); // seed pseudo-random number generator

for (int i = 0; i

myData[i] = rand() % 100; // pseudo-random value from 0 to

99.

}

void display_data()

{

cout << "Display data ";

for (int i = 0; i < N; i++)

{

cout << myData[i] << '\t';

if ( (i+1) % 5 == 0) cout << endl; // skip a line only after

5 numbers are displayed

//cout << myData[i] << endl;

}

}

void save_data(char const *filename)

{

cout << "saving Data ";

ofstream outfile;

outfile.open(filename, ios_base::out);

if (!outfile.is_open()) {

cout << "file could not be created ";

return;

// system("PAUSE");

};

cout << "Begin Processing File" << endl;

for (int i = 0; i

{

outfile << myData[i] << ' ';

}

outfile.close();

cout << "END Processing File" << endl;

} // end of save the data function

void load_data(char const *filename)

{

cout << "loading Data ";

ifstream infile;

// char const *filename = "myData.txt";

infile.open(filename, ios_base::in);

if (!infile.is_open()) {

cout << "file could not be created ";

return;

// system("PAUSE");

};

cout << "Begin Processing File" << endl;

for (int i = 0; i

{

infile >> myData[i];

}

infile.close();

cout << "END Processing File" << endl;