Question

C++ no std: cout but cout<<" ". also nothing ".h": in the header files: Also if statements should be used for the file portion. (filein.eof is not aloud)

generate integer random numbers and place them in a file. Each number on a single line. The numbers should range between 1-200 and the program should generate between 100-150 numbers. This means each time the program is executed, a file is created containing between 100-150 numbers with values between 1-200. Make sure you close the file once the numbers are generated. This should be done in a separate function B- The program should then read the file and create a dynamic array that holds the numbers. The size of the array is the number of elements in the file just read. This should be in a separate function.

Print values of the array: this should be done by creating a function that accepts two arguments, a const integer pointer to the array and size printValues(const int *arr, int size).

D- The main program should ask the user to enter a "key value" and then, -by a function call- find all numbers that are above that key value, store them in a dynamic array and return that array. Then your program should call the printValues function passing the new array. This should be implemented in as a pointer returning from a function (i.e. the function should return a pointer to the new array)

4- Print the array in reverse . Your program (via a function) should create a new copy of the array, except that the elements should be in reverse. The function should return a pointer to the new array. Then call printValues to show the values of the new array.

Answer 1

C++ PROGRAM:

#include <iostream>

#include <stdlib.h>

#include <time.h>   

#include <fstream>

using namespace std;

void RandomNumbers();

int* ReadFile(int&);

void printValues(const int*, int);

int* searchNumbers(const int*,int,int&);

int main() {

int *arr =NULL;

int arrSize;

RandomNumbers();

arr = ReadFile(arrSize);

cout<<"Initial array elements : "<<endl;

printValues(arr,arrSize);

int searchSize;

int *searchResults = searchNumbers(arr,arrSize,searchSize);

printValues(searchResults,searchSize);

return 0;

}

void RandomNumbers()

{

srand(time(NULL));

ofstream fileOut;

fileOut.open("beta.txt");

int n = rand()%50 +100;

int num;

for(int i=0;i<n-1;i++)

{

num = rand() % 199 + 1;

fileOut<<num<<endl;

}

num = rand()%199 +1;

fileOut<<num;

fileOut.close();

}

int* ReadFile(int &size)

{

ifstream fileIn;

fileIn.open("beta.txt");

int count=0;

int num;

int *arr;

if(fileIn.is_open())

{

while(!fileIn.eof())

{

fileIn>>num;

count++;

}

size=count;

fileIn.seekg (0, fileIn.beg);

arr = new int[size];

int i=0;

while(!fileIn.eof())

{

fileIn>>arr[i];

i++;

}

}else

cout<<"\n Unable to open file";

fileIn.close();

return arr;

}

void printValues(const int *arr, int n )

{

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

{

cout<<*(arr+i)<<endl;

}

}

int* searchNumbers(const int *arr,int n,int &searchSize)

{

int key;

int *searchResults ;

cout<<"\n Enter the key value : ";

cin>>key;

int count=0;

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

{

if(*(arr+i) > key)

count++;

}

searchResults = new int[count];

searchSize = count;

count=0;

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

{

if(*(arr+i) > key)

{

*(searchResults+count) = *(arr+i);

count++;

}

}

cout<<"Array with numbers > "<<key<<endl;

return searchResults;

}