Help me pass all tests. Do not change main.cpp and canvas.h. You can only make changes in a new canvas.cpp file.

---------------canvas.h--------------

#ifndef CANVAS_H #define CANVAS_H

#include

using namespace std;

// In this homework, you'll manipulate ASCII art images // consisting of a rectangular grid of chararacter pixels. class Canvas { public: // Allocates a canvas of the given width and height 5 that // consists entirely of ' ' (space) chars. If the width is 0, // the canvas is empty (pointer is NULL and _width is 0) Canvas(int width);

// Allocates a canvas with width 5 and height 5 that looks like: // // ### #### #### #### // # # # # # # # // ##### or #### or # or # # // # # # # # # # // # # #### #### #### // // depending upon which character ('A', 'B', 'C', or 'D') is // given as a parameter. If some other character is given, // allocates a canvas of ' ' chars with width 5 and height 5. Canvas(char x);

// Returns the width of the canvas. int width();

// Returns the entire canvas as a single string, consisting of each row // of the canvas, followed by the newline character (' '). // If the canvas is empty, returns an empty string. string to_string(); // Replaces every instance in the canvas of old_char with new_char. // For instance, if old_char is '#' and new char is '@', then: // // ### @@@ // # # @ @ // ##### becomes @@@@@ // # # @ @ // # # @ @ // void replace(char old_char, char new_char);

// Destructor. Deallocates all of the memory allocated by the canvas. ~Canvas();

// Allocates a canvas containing the sequence of characters // in the string with 2 columns of space between each pair // of adjacent characters. For instance, Canvas("BADCAB") // should yield: // // #### ### #### #### ### #### // # # # # # # # # # # # // #### ##### # # # ##### #### // # # # # # # # # # # # // #### # # #### #### # # #### // // Any characters in s not from {'A', 'B', 'C', 'D'} should be // replaced with empty 5x5 space, just like previous constructor. // If the string is empty (null string), the canvas is empty // (pointer is NULL and _width is 0) Canvas(string s);

// Adds a character to the Canvas's sequence of characters. void add(char x);

private: // A canvas is represented as a 2D char array, i.e. // an array of pointers to char (sub)arrays. // Each subarray corresponds to a COLUMN of the image. char** C; int _width; };

#endif

-------------main.cpp-------------------------

In this homework, you'll implement a class that represents "ASCII art" images and operations on them, represented as two-dimensional char arrays allocated on the heap (using the new operator). The following files are given to you: 1. A C++ header file (canvas.h) declaring the Canvas class. 2. A C++ source file (main.cpp) containing a main() function with tests. Create a new C++ source file named canvas.cpp that implements the class declared in canvas.h so that canvas.cpp and the provided files compile into a program that runs with no failed tests. "u\---@. + "u \- + \ ." ()[dad 7sa// // Test Canvas(string) Canvas C12("ADD"); test ( C12.width ()==19); + "\# \# \# \# \# \# " + "\#\#\#\#\# \# ### " + "\# \# \# \# \# \# " + "\# \# \#\#\#\# \#\#\#\# ); Canvas C13("VBAD!"); test ( C13.width ()==33); test( C13.to_string ()==string(" \#\#\#\# ###### n" ) + " ###### \# # n" + " \#\#\#\# \#\#\#\#\# \# \# + " ###### \#n" + " \#\#\#\# \# ####(n"); Canvas C14("DAD CAB"); test(C14.width ()==47); + "\# ########### " + "\#\#\#\# \# \#\#\#\#\# #####(n"); cout "Assignment complete." endl