Question

Write a C++ program that generates an array filled up with random positive integer number ranging from 15 to 20, and display it on the screen. After the creation and displaying of the array , the program displays the following:

[P]osition [R]everse, [A]verage, [S]earch, [Q]uit Please select an option: Then, if the user selects: -P (lowercase or uppercase): the program displays the array elements position and value pairs for all member elements of the array. -R (lowercase or uppercase): the program displays the reversed version of the array -A (lowercase or uppercase): the program calculates and displays the average of the array elements -S (lowercase or uppercase ): the program asks the user to insert an integer number and look for it in the array, returning the message wheher the number is found and its position ( including multiple occurences), or is not found. -Q (lowercase or uppercase): the program quits. NOTE: Until the last option (‘q’ or ‘Q’) is selected, the main program comes back at the beginning, asking the user to insert a new integer number.

Answer 1

• Firstly, create a random array using the rand() function and map it to a value between 15 and 20 by calculating : 15 + rand() % 5
• then, display the menu to the user. For each operation, we will pre define a fucntion to perform those tasks. In this program we will have these functions:
  • printArray(): to print array along with their position
  • printReverse(): to print the array in reverse
  • printAverage(): to print the average of array
  • searchArray(): to search for an element in array
• based on the user's choice these methods will be invoked. if the user enters 'Q" or 'q', the program terminates.

program:

#include <iostream>

using namespace std;

void printArray(int* a){
for(int i = 0; i<5; i++){
cout<<"\n";
cout<<"element at position "<<i+1<<": "<<a[i];
}
}

void printAverage(int* a){
float average = 0;
for(int i = 0; i<5; i++)
average += a[i];
average = (float)average/5;
cout<<"\n average of array elements = "<<average<<"\n";
}

void printReverse(int* a){
cout<<"\n";
for(int i = 4; i>=0; i--)
cout<<a[i]<<" ";
cout<<"\n";
}

void searchArray(int* a, int target){
int i;
for( i = 0; i<5; i++){
if(a[i]==target){
cout<<"Element found at index "<<i<<"\n";
break;
}
}
if(i==5)
cout<<"Element not found<<\n";
}
int main(){
int randArray[5];
for(int i = 0; i<5;i++){
randArray[i] = 15 + rand()%5;
}
char choice;
do{
cout<<"[P]osition\n";
cout<<"[R]everse\n";
cout<<"[A]verage\n";
cout<<"[S]earch\n";
cout<<"[Q]uit\n";
cout<<"Your choice: ";
cin>>choice;
switch(toupper(choice)){
case 'P':
printArray(randArray);
break;
case 'R':
printReverse(randArray);
break;
case 'A':
printAverage(randArray);
break;
case 'S':
int target;
cout<<"\nElement to be searched: ";
cin>>target;
searchArray(randArray, target);
break;
  
}
cout<<"\n";
}while(toupper(choice)!='Q');
}

console inputs and outputs:

[P]osition [R]everse [A]verage [S]earch [Q]uit Your choice: P element at position 1: 18 element at position 2: 16 element at position 3: 17 element at position 4: 15 element at position 5: 18 [P]osition [R]everse [A]verage [S]earch [Q]uit Your choice: 18 15 17 16 18 [P]osition [R]everse [A]verage [S]earch [Q]uit Your choice: a average of array elements = 16.8 [P]osition [R]everse [A]verage [S]earch [Q]uit Your choice: 5 Element to be searched: 17

Element to be searched: 17 Element found at index 2 [P]osition [R]everse [A]verage [S]earch [Q]uit Your choice: a