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#include <iostream>
#include <fstream>
#include <string>
#include <cstdlib>
using namespace std;
// function prototypes
int binarySearch(int array[], int size, int value);
void selectionSort(int array[], int size);
void swap(int &, int&);
const int SIZE = 200;
int main()
{
// prompt user to enter file name. also display if it exists or not
ifstream inputFile; // gives access to file
string name, filename;
int number;
const int SIZE = 200;
int values[SIZE];
int results;
// Get file name from the user
cout << "Enter the file name: ";
cin >> filename;
// Open the file
inputFile.open(filename.c_str());
// If the file opened successfully, process it
if (inputFile)
{
// Read the numbers from the file and display them.
while (inputFile >> number)
{
cout << number << endl;
}
// Close the file
inputFile.close();
}
else
{
// display an error message if the file was not found
cout << "Error opening the file.\n";
}
// display the unsorted array
cout << "The unsorted values:\n";
for (auto element : values)
cout << element << " ";
cout << endl;
// sort the array
selectionSort(values, SIZE);
cout << "The sorted values are\n";
for (auto element : values)
cout << element << " ";
cout << endl;
// prompt user to search for the number
cout << "Enter the number you're looking for or 0 to quit: ";
cin >> number;
// search for the number
results = binarySearch(int size, int value);
//Searches for # in the array
if(results == -1)
cout << "That number does not exist in the array.\n";
else{
cout << "That number was found at element " << results;
cout << " in the array.\n;"
}
else if (results == 0){
exit(EXIT_FAILURE);
}
return 0;
}
// prompt the user to enter a # to search the array or Q to quit
// swap function
void swap(int &a, int &b)
{
int temp = a;
a = b;
b = temp;
}
// sort the array using selection sort
void selectionSort(int array[], int size) // function used outside of main
{
int minIndex, minValue; // declaration
for(int start = 0; start < (size - 1); start++) // search begins from one element below the actual starting point
{
minIndex = start;
minValue = array[start];
for(int index = start + 1; index < size; index++) // incremented by one value at a time
{
if(array[index] < minValue)
{
minValue = array[index]; // locates element in position 0
minIndex = index;
}
}
swap(array[minIndex], array[start]);
}
}
// perform a binary search to locate the number, If found display
int binarySearch(const int array[], int size, int value) //
{
int first = 0, // First array element
last = size - 1, // Last array element
middle, // Mid point of search
position = -1; // Position of search value
bool found = false; // Flag
while(!found && first <= last)
{
middle = (first + last) / 2; // Calculate mid point
if(array[middle] == value) // If value is found at mid
{
found = true;
position = middle;
}
else if(array[middle] > value) // If value is in lower half
last = middle - 1;
else
first = middle + 1; // If value is in upper half
}
return position;
}
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