To be done in Objective Caml 1 Compute the perimeter of a s

To be done in Objective Caml.

# 1. Compute the perimeter of a shape represented by a list of points. Your function should have the type (float * float) list -> float. Also include the distance between the first point in the list and the last point in the list. So when our recursive function gets to the base case of having just one more point in the list, it must have access to the first point in the list so that we can return the distance between the first and last points. Write a helper function in a let-expression nested in your definition of perimeter that carries along the value of the first point until it is needed

#2. Write a function with type int list list -> int -> int list list that implements matrix scalar addition. This is the operation of adding the integer value to each element of the matrix.

Solution

import java.util.Scanner; import java.util.InputMismatchException; import java.io.File; import java.io.FileNotFoundException; import java.io.PrintWriter; /** * Implements a Grocery List Version 4: Has code for all methods (final version) * * @author William McDaniel Albritton */ public class GroceryListProgram4 { /** * The main() Method Starts The Program. * * @param commandlineArguments 1st argument is INPUT File, 2nd argument is OUTPUT File */ public static void main(String[] commandlineArguments) { // Error Checking For 2 Command Line Arguments.. if (commandlineArguments.length != 2) { System.out.println(\"Please enter the INPUT file name as \" + \"the 1st commandline argument.\"); System.out.println(\"Please enter the OUTPUT file name as \" + \"the 2nd commandline argument.\"); System.out.println(\"Please enter exactly \" + \"two (2) commandline arguments.\"); }// end of if // if no commandline argument errors, continue program else { // Declare and instantiate array of 100 Strings final Integer MAX_SIZE = new Integer(100); String groceryList[] = new String[MAX_SIZE]; // Set size of grocery list to zero (0) items Integer size = new Integer(0); // read grocery items from file & store in array for grocery list try { size = GroceryListProgram4.readFromFile(commandlineArguments[0], groceryList, size); } catch (ArrayIndexOutOfBoundsException exception) { System.out.print(\"ERROR: Too many items in input file. \"); System.out.println(\"Please limit to \" + MAX_SIZE + \" items.\"); // Immediately terminates program System.exit(1); } // user\'s choice for Menu Integer choice = new Integer(0); // choice for ending program final Integer QUIT = new Integer(4); // if the user does not want to QUIT, keep looping while (!choice.equals(QUIT)) { // get the user\'s choice choice = GroceryListProgram4.displayMenu(); // add grocery item if (choice.equals(1)) { size = GroceryListProgram4.add(groceryList, size); } // delete grocery item else if (choice.equals(2)) { size = GroceryListProgram4.delete(groceryList, size); } // display grocery item else if (choice.equals(3)) { GroceryListProgram4.display(groceryList, size); } // error message else if (!choice.equals(QUIT)) { System.out.println(\"ERROR: Please enter an integer in the range from 1 to 4\"); } }// end of \"while\" // write to from grocery list array to OUTPUT file GroceryListProgram4.writeToFile(commandlineArguments[1], groceryList, size); }// end of \"else\" }// end of main() method /** * Displays the menu for the program and returns user\'s choice * * @return the choice of the user (if error, returns 0) */ public static Integer displayMenu() { // display menu System.out.println(); System.out.println(\"\\tGROCERY LIST MENU\"); System.out.println(\"\\t Enter 1 to Add\"); System.out.println(\"\\t Enter 2 to Delete\"); System.out.println(\"\\t Enter 3 to Display\"); System.out.println(\"\\t Enter 4 to Quit\"); System.out.print(\"\\tEnter your choice: \"); // get input from user Scanner keyboardInput = new Scanner(System.in); Integer choiceOfUser = new Integer(0); try { // non-integer input will throw InputMismatchException choiceOfUser = keyboardInput.nextInt(); } catch (InputMismatchException exception) { // Already have error message in main() method, // as choiceOfUser = 0 } System.out.println(); return choiceOfUser; } /** * Reads grocery items from a file and stores items in an array * * @param inputFile is the INPUT File * @param array is the Grocery List array * @param size is the number of items in Grocery List * @return the new size of the grocery list * @throws ArrayIndexOutOfBoundsException if array size is less than number of * items in input file */ public static Integer readFromFile(String inputFile, String[] array, Integer size) throws ArrayIndexOutOfBoundsException { // connect to file (does NOT create new file) File file = new File(inputFile); Scanner scanFile = null; try { scanFile = new Scanner(file); } catch (FileNotFoundException exception) { // Print error message. // In order to print double quotes(\"), // the escape sequence for double quotes (\\\") must be used. System.out.print(\"ERROR: File not found for \\\"\"); System.out.println(inputFile + \"\\\"\"); } // if made connection to file, read from file if (scanFile != null) { // keeps looping if file has more lines.. while (scanFile.hasNextLine()) { // get a line of text.. String line = scanFile.nextLine(); // display a line of text to screen.. // System.out.println(line); // array[0] stores the first row (headings) to table array[size] = line; // increment size ++size; } // In order to print double quotes(\"), // the escape sequence for double quotes (\\\") must be used. System.out.println(\"Read from file \\\"\" + inputFile + \"\\\"\"); }// end of \"if\" for connecting to file return size; } /** * Adds a grocery item to an array * * @param list is the grocery list * @param listSize is the size of the grocery list * @return new size of the grocery list */ public static Integer add(String[] list, Integer listSize) { // get item from user Scanner keyboard = new Scanner(System.in); System.out.print(\"Enter name of item: \"); String name = keyboard.nextLine(); System.out.print(\"Enter number of items: \"); String number = keyboard.nextLine(); // add to the end of the array list[listSize] = name + \", \" + number; // add one to the size (one item to end of list) return listSize + 1; } /** * Deletes a grocery item from an array * * @param list is the grocery list * @param listSize is the size of the grocery list * @return new size of the grocery list */ public static Integer delete(String[] list, Integer listSize) { // get user input System.out.print(\"Enter the row number of the item you wish to delete: \"); Scanner keyboard = new Scanner(System.in); try { // throws an exception if not an integer Integer row = keyboard.nextInt(); // check for negative integers if (row <= 0) { System.out.println(\"ERROR: The integer cannot be negative or zero.\"); } // check for integer too big else if (row > listSize - 1) { System.out.println(\"ERROR: The integer is too big for the list.\"); } else { // delete item by shifting items on the right of the item to the left for (int i = row; i < listSize; i++) { list[i] = list[i + 1]; } // subtract one from the size (one item deleted from list) --listSize; } } catch (InputMismatchException exception) { System.out.println(\"ERROR: You must enter an integer to delete an item.\"); } return listSize; } /** * Displays a grocery list * * @param list is the grocery list * @param listSize is the size of the grocery list */ public static void display(String[] list, Integer listSize) { // loop through the array for (int i = 0; i < listSize; i++) { // display headings if (i == 0) { System.out.println(\"Row \" + list[i]); } // display grocery list items as a numbered list else { System.out.println(i + \". \" + list[i]); } } } /** * Write grocery list array to file * * @param outputFile is the name of the output file * @param list is the grocery list * @param listSize is the size of the grocery list */ public static void writeToFile(String outputFile, String[] list, Integer listSize) { // \"PrintWriter\" is a Class Used To Write to A File. PrintWriter fileWriter = null; try { /* * Must use try-catch block, because PrintWriter may throw * FileNotFoundException, which is a checked exception. This will connect * to a file in the current directory. If the file does not exists, a new * file will be created. If the file does exists, the file will be * overwritten. */ fileWriter = new PrintWriter(outputFile); } catch (FileNotFoundException exception) { // Print error message. // In order to print double quotes(\"), // the escape sequence for double quotes (\\\") must be used. System.out.print(\"ERROR: File not found for \\\"\"); System.out.println(outputFile + \"\\\"\"); } // if file opened successfully, then below code executes.. // continue program if writeToFile is not \"null\" if (fileWriter != null) { // loop through list (grocery list) and write to file for (int i = 0; i < listSize; i++) { fileWriter.println(list[i]); } // REMEMBER: always give feedback to the user! System.out.println(\"Wrote to file \\\"\" + outputFile + \"\\\"\"); // WARNING: don\'t forget to close the file! // will not write to file if not closed! fileWriter.close(); }// end of \"if\" statement for writeToFile } }// end of class