Introduction to C++ Homework Problem Set 5

project.cpp

/* Introduction to C++ Homework Problem Set 5 Project by Dillon Morse
 * ------------------------------------------------------------------
 * Create a sequential file that contains 34 rows and 34 columns. Fill the
 * array with random numbers between -20 and 80. Your main code will ask the
 * user to enter a number N between -20 and 80. Yoiu will open the file and
 * search the two dimension array you read in for the number N. If found,
 * display the number of times it was found. Next, pass your two dimension
 * array to a functoin called diagonal. The function will ask the user if they
 * want the sum of the main diagonal values to a function called diagonal. The
 * function will ask the user if they want the sum of the main diagonal values
 * or the sum of the off diagonal values.
 */

#include <iostream>
#include <fstream>
#include <ctime>
#include <cstdlib>

using namespace std;

void create_file();
int get_input( int& );
int search_file( int, int** );
int** derive_array();
int diagonal( int**, int );

int main(int argc, char const* argv[])
{
  int response_1;
  int pass = 1;

  srand( time(0) );

  create_file();
  cout << search_file( get_input( pass ), derive_array() ) << endl;
  cout << diagonal( derive_array(), get_input( pass ) ) << endl;

  return 0;
}

void create_file() {
  ofstream file_out ( "file.txt" );

  if ( file_out.is_open() ) {
    for ( int j = 0; j < 34; j++ ) {
      for ( int k = 0; k < 34; k++ ){
        file_out << rand() % 101 - 20 << endl;
      }
    }
  }
}

int get_input( int& pass ) {
  int input;
  enum diagonal {
    main,
    off
  };

  switch ( pass ) {
    case 1:
             cout << "Enter a number between -20 and 80" << endl;
               break;
    case 2:
             cout <<
                 "Would you like to sum the main diagonal or the off diagonal?"
               << endl
               << "Enter 'main' or 'off'"
               << endl;

               break;
  }

  cin >> input;

  pass++;

  return input;
}

int** derive_array() {
  ifstream file_in ( "file.txt" );
  string line;
  int pos_1 = 0;
  int pos_2 = 0;

  // Allocate memory for a 2D array arr
  int** arr = new int* [34];
  for ( int i = 0; i < 34; i++ ) {
    arr[i] = new int[34];
  }

  if ( file_in.is_open() ) {
    while ( getline ( file_in, line ) ) {
      if ( pos_2 == 34 ) {
        pos_1++;
        pos_2 = 0;
      }

      arr[pos_1][pos_2] = atoi( line.c_str() );

      pos_2++;
    }
  }

  return arr;
}

int search_file ( int input, int** arr ) {
  int times_found = 0;

  for ( int j = 0; j < 34; j++ ) {
    for ( int k = 0; k < 34; k++ ) {
      if ( arr[j][k] == input ) times_found++;
    }
  }

  // Unallocate memory for arr
  for ( int i = 0; i < 34; i++ ) {
    delete[] arr[i];
  }
  delete[] arr;

  return times_found;
}

int diagonal ( int** arr, int input  ) {
  int sum = 0;

  enum diagonal {
    main,
    off
  };

  switch (input) {
    case main:
             for ( int i = 0; i < 34; i++ ) {
               sum += arr[i][i];
             }
               break;
    case off:
             for ( int i = 34; i < 0; i-- ) {
               sum += arr[i][i];
             }
               break;
  }

  // Unallocate memory for arr
  for ( int i = 0; i < 34; i++ ) {
    delete[] arr[i];
  }
  delete[] arr;

  return sum;
}