Question

in C++ please

A publisher may allow a reader to select a subset of chapters to purchase. Given 15 integers that are 0 or 1 indicating whether or not to include chapters 1 to 15, output the selection using shorthand for ranges of 3 or more (11, 12, 13 becomes 11-13). If the input is 111101 011011100, the output should be: 1-46 8 9 11-13 If no chapters are selected, output: None For simplicity, follow every term including the last by one space (and end with newline). Hints: • This problem is hard. Start by creating a for loop that just prints the selected chapters one by one, without shorthands for ranges. Your program will pass a few test cases. . Next, extend the loop body to handle the case for a range of 3. Use an if statement to lookahead from index i to i+1 and i+2. If all three elements are 1's, print the range. Be careful to only do the lookahead if the current i is 13 or less. If the current index is 14 (or 15), there's no need to lookahead; the range can't be 3 or more because only 15 chapters exist. If your loop body printed a range like 2-4, don't forget to update your loop's index i to be 4 (don't leave it at 2). • One you get the above working, then use a nested while loop to detect even larger ranges, such as 2-7. And don't forget to update the for loop index i to the detected range end. • Use a boolean variable, initialized to false, and in your for loop set it to true if any chapter is selected. After your for loop above, if the variable is still false, print "None".

Answer 1

// C++ program to display the selection of pages using shorthand ranges of 3 or more.
#include <iostream>

using namespace std;

int main()
{
int pages[15]; // create array of size 15
int i,j;
// loop to take input for 15 pages (0/1)
cout<<"Enter 0 for not including and 1 for including chapter (for 15 chapters): "<<endl;
for(i=0;i<15;i++)
{
cin>>pages[i];
}

bool pagesIncluded = false;

// loop 15 times
for(i=0;i<15;)
{
// if ith pages is included
if(pages[i] == 1)
{
pagesIncluded = true; // set pagesIncluded to true
// loop from i+1 to maximum 15 or when jth value is 0
for(j=i+1;j<15;j++)
{
if(pages[j] == 0) // if jth value is 0, exit from inner for loop
{
break;
}
}

// if number of 1 entries is 3 or more, then output it as a shorthand range and set i to j+1
if((j-1-i+1) >= 3)
{
cout<<(i+1)<<"-"<<j<<" ";
i = j+1;
}else
{
// if number of 1 entries is less than 2, then output (i+1) position and increment i by 1
cout<<(i+1)<<" ";
i++;
}
}else // if it entry is 0, increment i by 1
i++;
}

// if no pages are included, display None
if(!pagesIncluded)
cout<<"None";

cout<<endl; // display a new line at the end
return 0;
}

//end of program

Output:

Enter o for not including and 1 for including chapter (for 15 chapters): 1111 0 1 0 1 1 0 1 1 1 0 0 1-4 6 8 9 11-13

Enter o for not including and 1 for including chapter (for 15 chapters): 00111 001111 0111 3-5 8-11 13-15