Description
Purpose
This project is designed to teach you how to devise, implement, and submit solutions to the simple programming problem of constructing a “todo list software”. It aims at making sure that you master the simple concepts of control structures and data manipulation before introducing more advanced concepts.
Challenge
In short
Develop a simple program that asks the user to provide their todo list, and then tracks the completion of the items (or “tasks”) on that list.
In more details
-
Your program should start by asking the user to provide items for their todo list, one by one.
-
Once the user is done providing the items, it should display the todo list, with a number associated to each item, and its status (done or not done).
-
Then, your program should ask the user to enter the number of the item they have just completed. There are three cases:
- If the user enters something that is not a number, your program should simply ask again.
- If the user enters an “invalid” number (that is, that does not correspond to the number of an item), your program should ask again.
- If the user enters the number of an item that is not done, its status should become “done”.
-
Once the user entered the number of item, the updated todo list should be displayed, and the user should be asked for another number of an item.
-
Once the user completed all the items in the list, the program should display a celebratory message about being done.
Submission
Please, follow our guideline on project submission. In particular, make sure you write your name and the date in a delimited comment at the beginning of your file.
Example
Here is an example of execution, where the user input is u͟n͟d͟e͟r͟l͟i͟n͟e͟d͟, and hitting “enter” is represented by “⏎͟”:
What is on your todo list? Enter "done" when you are done.
M͟a͟k͟e͟ ͟s͟u͟r͟e͟ ͟m͟y͟ ͟I͟D͟E͟ ͟i͟s͟ ͟s͟t͟i͟l͟l͟ ͟w͟o͟r͟k͟i͟n͟g͟.͟⏎͟
What is on your todo list? Enter "done" when you are done.
C͟o͟m͟p͟i͟l͟e͟ ͟a͟ ͟s͟i͟m͟p͟l͟e͟ ͟"͟H͟e͟l͟l͟o͟ ͟W͟o͟r͟l͟d͟"͟ ͟p͟r͟o͟g͟r͟a͟m͟.͟⏎͟
What is on your todo list? Enter "done" when you are done.
S͟t͟a͟r͟t͟ ͟w͟o͟r͟k͟i͟n͟g͟ ͟o͟n͟ ͟t͟h͟i͟s͟ ͟p͟r͟o͟j͟e͟c͟t͟.͟⏎͟
What is on your todo list? Enter "done" when you are done.
d͟o͟n͟e͟⏎͟
Here is your current todo list:
| # | Status | Task |
| 1 | ☐ | Make sure my IDE is still working.
| 2 | ☐ | Compile a simple "Hello World" program.
| 3 | ☐ | Start working on this project.
Enter the number of the task you completed.
N͟o͟t͟ ͟y͟e͟t͟.͟⏎͟
Enter the number of the task you completed.
1͟⏎͟
Here is your current todo list:
| # | Status | Task |
| 1 | ☑ | Make sure my IDE is still working.
| 2 | ☐ | Compile a simple "Hello World" program.
| 3 | ☐ | Start working on this project.
Enter the number of the task you completed.
3͟⏎͟
Here is your current todo list:
| # | Status | Task |
| 1 | ☑ | Make sure my IDE is still working.
| 2 | ☐ | Compile a simple "Hello World" program.
| 3 | ☑ | Start working on this project.
Enter the number of the task you completed.
4͟ ⏎͟
Enter the number of the task you completed.
2͟⏎͟
You're all done, congratulations!
Press any key to continue...Bonuses
- The behaviour of the program if the user enters the number of an item whose status is “done” is not specified above. Write (as a comment) in your program which behaviour you implemented, and test it.
- Complete the project without resizing arrays.
- Improve the way the todo list is displayed using string formatting.
- Display, along with the list of items, the completion rate: for example, after the user completed the first of their list of 4 items, the program should display “You are 25% done!“.
Submission
Please, follow our guideline on project submission. In particular, make sure you write your name and the date in a delimited comment at the beginning of your file.
Solution
Simplest Solution
A possible solution, using arrays but not resizing them, is as follows:
using System;
public class Program
{
public static void Main(string[] args)
{
// Variable declarations.
string[] todo = new string[100]; // This will hold the items in the todo list.
// Note that we are arbitrarily deciding that the maximum number of items is 100.
bool[] status = new bool[100]; // This will hold the status of each item.
// true means "done", false means "not done".
string uInput; // This will hold user input.
int todoSize = 0; // This will hold the actual number of items in the list.
int completed = 0; // This will hold the number of items done.
int justdone; // This will hold the number of the last item completed.
bool valid; // This will hold true if the user input is valid (a positive number
// less than the number of items in the list), false otherwise. Used for user-input
// validation.
char itemStatus; // This will hold '☑' if the current item is done,
// '☐' otherwise.
// We start by populating the list with items.
do
{
Console.WriteLine(
"What is on your todo list? Enter \"done\" when you are done."
);
uInput = Console.ReadLine();
if (uInput != "done")
{
todo[todoSize] = uInput; // We can store the first item at index todoSize
// since its initial value is 0.
todoSize++; // We increment the number of items in the list.
}
} while (uInput != "done"); // When the user enters "done", we exit this loop.
// We now display the todo list, and ask the user to indicate which item they
// completed, as long as there are some items left in their list.
while (completed != todoSize)
{
// We display the todo list.
Console.WriteLine("Here is your current todo list:");
Console.WriteLine("| # | Status | Task |");
for (int i = 0; i < todoSize; i++)
{
if (status[i])
{
itemStatus = '☑';
}
else
{
itemStatus = '☐';
}
Console.WriteLine(
"| "
+ (i + 1)
+ " | "
+ itemStatus
+ " | "
+ todo[i]
);
}
// We now ask the user to enter the number of the completed item.
valid = false; // We assume that the user has not given a valid value yet.
do
{
Console.WriteLine(
"Enter the number of the task you completed."
);
valid =
int.TryParse(Console.ReadLine(), out justdone)
&& 0 < justdone
&& justdone <= todoSize;
} while (!valid);
status[justdone - 1] = true; // We indicate that the item was completed by setting its value to true.
completed++; // We increment the number of items completed.
Console.WriteLine(
$"You are {completed / (double)todoSize:P} done!"
);
// Note that we force double division using casting, and use the :P format speficier.
}
Console.WriteLine("Congratulations!");
}
}You can download it here
Using Classes
Another solution is to create a class for “todo list items” and to
create an array of them. That is, have a class file Todo.cs along the
lines of
class Todo{
public string Description{get; set;}
public bool Status{get; set;}
}and then to create and manipulate arrays of Todo objects, for example
as follows:
Todo[] todoList = new Todo[100];
todoList[0] = new Todo();
todoList[0].Description = "My first item";
todoList[0].Status = false;
Console.Write(todoList[0].Description + (todoList[0].Status ? " done" : " not done"));