Basic array problems

Consider this data file: numbers.txt.

Write the following programs:

  1. min & max (solution: min & max)
  2. average (solution: average)
  3. standard deviation (solution: standard deviation)

Various array problems

Setting the context

Start with the following partial program: 

#include <iostream>
using namespace std;

int main()
{
  // read size n, allocate array of n doubles, read values into array
  int n;
  cin >> n;
  double * A = new double[n];
  for(int i = 0; i < n; i++)
    cin >> A[i];

  // Now what?

  return 0;
}
... and add code after the "Now what?" comment to solve one of the problems below for the array A of n elements created in the first part of the code.

Problem 1: Find the index of the minimum element

Print out the index of the minimum element in the array. So, for example: 
~/$ ./ex1a
4
34 12 8 29
minimum element is A[2] = 8.
solution

Problem 2: Printing the elements

Print elements of the array, separated by commas. So, for example: 
~/$ ./ex1b
4
34 12 8 29
A = [34, 12, 8, 29]
solution

[Mandatory Practice Problem] Problem 3: Splitting an array into two arrays

Split positive and negative. I actually want you to create two new arrays: Then, your program should print out each array as follows: 
~/$ ./ex1d
10
0 1 2 -3 4 -5 -6 7 8 9
negative: -3 -5 -6
positive: 1 2 4 7 8 9
solution

Other problems

  1. Create and print array of the "partial differences" of consecutive elements in the array. Here's an example of a sequence of four numbers along with the sequence of partial differences (note that there are only three elements in that sequence). 
    3  7   8   5
\_/ \_/ \_/
 4   1  -3
    A run of your program should look like this: 
    ~/$ ./ex1c
4
14 16 8 29
2 -8 21
    solution
  2. histograms (arrays of counters)
  3. masks (i.e. an array of bools), for example to implement a simple hangman game.