If statement not working in C# - c#

I'm using a tutorial to write a simple app that calculates how many years it will take for a bank account to reach a target amount.
I'm trying to use an "If" statement, so if the person's beginning balance is more than their target amount, it prints "Your balance is bigger than the target amount", but when I write this into my code, it always prints the above no matter what amounts the user inputs.
Here's the code:
double balance, interestRate, targetBalance; //creating three doubles
Console.WriteLine("What is your current balance?"); //writing to the console
balance = Convert.ToDouble(Console.ReadLine()); //reading what the user inputs & converting it to a double
Console.WriteLine("What is your current annual interest (in %)?");
interestRate = 1 + Convert.ToDouble(Console.ReadLine()); //same as above
Console.WriteLine("What balanec would you like to have?");
targetBalance = Convert.ToDouble(Console.ReadLine()); //same as above
int totalYears = 0; //creates an int variable for the total years
do
{
balance *= interestRate; //multiplying balance x interest rate
++totalYears; // adding 1 to the total years
}
while (balance < targetBalance); //only do the above when balance is less than target balance
if (balance < targetBalance)
{
Console.WriteLine("In {0} year{1} you'll have a balance of {2}.", totalYears, totalYears == 1 ? "" : "s", balance); //writing the results to the console
}
else if (targetBalance < balance)
{
Console.WriteLine("Your balance is bigger than the target amount");
}
Console.ReadKey(); //leaving the results there until the user inputs a key

The only way for your do-while loop to exit is when the balance is >= the target balance. Because of this, your first if statement will never evaluate to true.
You probably want to do your targetBalance < balance check before you enter your do-while loop. If the balance is greater than the target, start over. And then after the loop, there is no need to do the if check around your 'In x years...' dialog.

It works fine here.
But please check your balance,targetBalance first. You didn't notice that what would happen If they are equal.

I think you want this...
double balance, interestRate, targetBalance; //creating three doubles
Console.WriteLine("What is your current balance?"); //writing to the console
balance = Convert.ToDouble(Console.ReadLine()); //reading what the user inputs & converting it to a double
Console.WriteLine("What is your current annual interest (in %)?");
interestRate = 1 + Convert.ToDouble(Console.ReadLine()); //same as above
Console.WriteLine("What balanec would you like to have?");
targetBalance = Convert.ToDouble(Console.ReadLine()); //same as above
int totalYears = 0; //creates an int variable for the total years
if (balance < targetBalance)
{
do
{
balance *= interestRate; //multiplying balance x interest rate
++totalYears; // adding 1 to the total years
}
while (balance < targetBalance); //only do the above when balance is less than target balance
Console.WriteLine("In {0} year{1} you'll have a balance of {2}.", totalYears, totalYears == 1 ? "" : "s", balance); //writing the results to the console
}
}
else if (targetBalance < balance)
{
Console.WriteLine("Your balance is bigger than the target amount");
}
Console.ReadKey(); //leaving the results there until the user inputs a key

Related

How do I add the last typed number to a total?

I'm new to learning C# and I was wondering how to keep adding numbers I type to a total number. Right now instead of adding up all the numbers I typed in before typing 0, it just takes the last typed in number... The number count does go up however, which is why I'm pretty confused.
For example:
Enter number: 2
Enter number: 6
Enter number: 4
Enter number: 7
Enter number: 0
There are 4 positive numbers (Works like I intended)
The total amount is 7 (Is supposed to be 2+6+4+7 = 21)
Console.Write("Enter number: ");
string numberInput = Console.ReadLine();
double number = double.Parse(numberInput);
int count = 0;
double begin = 0;
double total = 0;
while (number != 0)
{
if (number >= 0)
{
count++;
total = begin + number;
}
Console.Write("Enter number: ");
number = double.Parse(Console.ReadLine());
}
double average = total / count;
Console.WriteLine("There are {0} positive numbers", count);
Console.WriteLine("The total amount is {0}", total);
Console.WriteLine("Your average is: {0}", average);
Console.ReadKey();
I figured it out already, had to change this:
total = begin + number;
to
total = total + number;
You don't need to use begin variable as you can sum input values like below:
total += number; // This is the same with 'total = total + number;'
As a suggestion, you can improve your code using do while loop like below:
int count = 0;
double total = 0;
double number;
do
{
Console.Write("Enter number: ");
number = double.Parse(Console.ReadLine());
if (number > 0)
{
count++;
total += number;
}
} while (number != 0);
double average = total / count;
Console.WriteLine("There are {0} positive numbers", count);
Console.WriteLine("The total amount is {0}", total);
Console.WriteLine("Your average is: {0}", average);
Console.ReadKey();

How do I sum up every 5th number instead of all numbers?

I need some help with the for-loop. I'm trying to sum up every fifth number that I type in, instead it sums them all up. What do I have to change?
int count = 0;
double total = 0;
Console.Write("Enter your number: ");
int input = int.Parse(Console.ReadLine());
while (input != 0)
{
count++;
for (count = 0; count <= 0; count += 5)
{
total = total + input;
}
Console.Write("Enter your number: ");
input = int.Parse(Console.ReadLine());
}
Console.WriteLine("The sum of every +5 numbers is: {0}", total);
Console.ReadKey();
Assuming that you enter a list of numbers, and the 1st number and every five afterwards is added (so 1st, 6th, 11th, etc.):
int count = 0;
double total = 0;
Console.Write("Enter your number: ");
int input = int.Parse(Console.ReadLine());
while (input != 0)
{
count++;
if (count % 5 == 1)
total = total + input;
Console.Write("Enter your number: ");
input = int.Parse(Console.ReadLine());
}
Console.WriteLine("The sum of every +5 numbers is: {0}", total);
Console.ReadKey();
This works by using the modulo operator (%). The modulo operator returns the remainder of a division operation involving the number you specify.
In the code if (count % 5 == 1), the question is:
Is the remainder of count divided by 5 equal to 1?
If so, it adds the number. If not, it is skipped
The reason the remainder is one is because we want results 1, 6, 11, etc:
1 / 5 = remainder 1
6 / 5 = remainder 1
11 / 5 = remainder 1
If you change the modulo value to 0 it will return the results at position 5, 10, 15, etc.
You could just store the numbers in a list and calculate it at the end:
var numbers = new List<int>();
Console.Write("Enter your number: ");
var input = int.Parse(Console.ReadLine());
while (input != 0)
{
numbers.Add(input);
input = int.Parse(Console.ReadLine());
}
var total = numbers.Where((x, i) => (i + 1) % 5 == 0).Sum(); // i + 1 since indexes are 0-based.
Console.WriteLine("The sum of every +5 numbers is: {0}", total);
You can try this:
double total = 0;
int passover = 4;
int input = 0;
do
{
passover++;
Console.Write("Enter your number: ");
int.TryParse(Console.ReadLine(), out input);
if ( passover != 5 ) continue;
passover = 1;
total = total + input;
}
while ( input != 0 );
Console.WriteLine("The sum of every fifth numbers is: {0}", total);
Console.ReadKey();
I think the best way is to recover all the values ​​before making the sum, this code works:
double total = 0;
int input = -1;
List<int> allInput = new List<int>();
while (input != 0)
{
Console.Write("Enter your number: ");
input = int.Parse(Console.ReadLine());
allInput.Add(input);
}
for (int i = 0; i < allInput.Count()-1; i += 5)
{
total = total + allInput[i];
}
Console.WriteLine("The sum of every +5 numbers is: {0}", total);
Console.ReadKey();
Your sample would go forever, because there is no break point in your loop. You should always put a break point in your loop, otherwise it'll loop indefinitely.
Here is what you need :
int total = 0;
int count = 0;
Console.Write("Enter your number: ");
while (true)
{
int input = 0;
bool isNumber = int.TryParse(Console.ReadLine(), out input);
if (isNumber)
{
count++;
if (count % 5 == 0)
total += input;
}
else
{
break;
}
Console.Write("Add another number or press enter to get the sum : ");
}
Console.WriteLine("The sum of every +5 numbers is: {0}", total);
Console.ReadKey();
So, you'll need first to put the user input inside a loop, and keep asking the user for adding another number until hits the condition where you close this loop. In the example, I decided to break the loop if the user typed anything not a number. but I told the user to press enter to get the some, to end the loop. For you, you'll need to translate that to your application breakpoint, how would you want the user to get the sum ?. Then, change the condition to your logic, so it breaks the loop and gets the sum.
another point is that int.TryParse. When you want to convert strings to numbers (int, long, decimal ..etc). You should always use `TryParse, this will verify the number, if the conversion failed, it'll return false. This way you can maintain the conversion and do something about it.

How to populate a 2d array via user input?

I'm trying to create a 5,4 array in C# where each cell is made up of user data. The code I have below works sometimes, but not consistently. I can input data into cell [4,5] or [3,4] for example. However, sometimes when I run the code It does not accept the data and displays an empty cell. and Any tips?
decimal[,] departments = new decimal[4, 5];
//int count = 0;
Console.WriteLine("If you would like to run the program, type enter");
string exit = Console.ReadLine();
while (exit != "yes")
{
Console.WriteLine("What is the department number that you would like to enter sales for? Enter 9 to exit");
int departmentNo = int.Parse(Console.ReadLine());
Console.WriteLine("What day would you like to enter sales for?");
int input = int.Parse(Console.ReadLine());
Console.WriteLine("Enter sales");
departments[departmentNo, input] = decimal.Parse(Console.ReadLine());
Console.WriteLine("If you are finished, enter yes");
exit = Console.ReadLine();
}
Example output
0 0 0 0
0 0 0 0
0 0 500 0
500 0 0 0
You can use .GetUpperBound(dimension) to obtain the maximum bound (in the example below, it will return 1 for each dimension) for a specific dimension. Once you've got that, you just need to go through each position (I'm assuming you just need to fill data at each position).
Here's a sample:
int[,] items = new int[2, 2];
int width = items.GetUpperBound(0) + 1;
int height = items.GetUpperBound(1) + 1;
for (int x = 0; x < width; ++x)
{
for (int y = 0; y < height; ++y)
{
string input;
int inputValue;
do
{
Console.WriteLine($"Please input value for ({x},{y}): ");
}
while (!int.TryParse(input = Console.ReadLine(), out inputValue));
items[x, y] = inputValue;
}
}
Or if you do need the user to be able to specify where the sales value goes, you can update your code to add some validation checks:
while (exit != "yes")
{
Console.WriteLine("What is the department number that you would like to enter sales for? Enter 9 to exit");
int departmentNo = int.Parse(Console.ReadLine());
if (departmentNo > departments.GetUpperBound(0) || departmentNo < 0)
{
Console.WriteLine("Please enter a valid department number.");
continue;
}
Console.WriteLine("What day would you like to enter sales for?");
int input = int.Parse(Console.ReadLine());
if (input > departments.GetUpperBound(1) || input < 0)
{
Console.WriteLine("Please enter a valid input.");
continue;
}
Console.WriteLine("Enter sales");
if (!decimal.TryParse(Console.ReadLine(), out decimal value))
{
Console.WriteLine("Please enter a valid sales figure.");
continue;
}
departments[departmentNo, input] = value;
Console.WriteLine("If you are finished, enter yes");
exit = Console.ReadLine();
}
You probably want to change it to be similar to my example above so that you don't have to restart the entire loop again if the input is bad.
Because the departments has a fixed length of [4,5], it means the departmentNo can only be in range 0-3 and the input can only be in range 0-4. In addition, decimal keyword indicates a 128-bit data type, it's mean the value for a cell is in range ±1.0 x 10^28 to ±7.9228 x 10^28, which means 28-29 significant digits approximately. You should make some if conditions to make sure input values are in available range.

add digits of each double digit numner

Here is my code. I want to have users enter any number of doubles continuously until 100 times (could be however number of times the user wants but less than 100). Display sum of all values entered. In my code, I don't know how to allow users to enter numbers continuously (im guessing you would have a while loop).
Thanks a lot!
Console.WriteLine("Enter double");
double.first = double.Parse(Console.ReadLine());
while(first != 0)
{
Console.WriteLine("Enter double");
int num = int.Parse(Console.ReadLine());
double sum;
while(num != 0)
{
double ten = num/10;
double tenth = Math.Floor(ten);
double oneth = num % 10;
sum = tenth + oneth;
Console.WriteLine("{0}", sum);
break;
}
first = double.Parse(Console.ReadLine());
}
I want to have users enter any number of doubles continuously until
100 times (could be however number of times the user wants but less
than 100).
You need to keep track of 3 things.
The next double.
The running total.
How many times the user has provided input.
Variables:
double next;
double runningTotal = 0;
int iterations = 0;
Now, to continuously receive input from the user, you can write a while-loop as you correctly identified. In this loop you should check for two things:
That the next value is a double and that it is not 0.
That the user has not provided input more than 100 times.
While-loop:
while (double.TryParse(Console.ReadLine(), out next) && next != 0 && iterations < 100) {
// Count number of inputs.
iterations++;
// Add to the running total.
runningTotal += next;
}
Display sum of all values entered.
Simply write to the console.
Output:
Console.WriteLine("You entered {0} number(s) giving a total value of {1}", iterations+1, runningTotal);
Complete example:
static void Main()
{
double runningTotal = 0;
double next;
var iterations = 0;
Console.Write("Enter double: ");
while (double.TryParse(Console.ReadLine(), out next) && next != 0 && iterations < 100)
{
runningTotal += next;
iterations++;
Console.Write("Enter double: ");
}
Console.WriteLine("You entered {0} number(s) giving a total value of {1}", iterations+1, runningTotal);
Console.Read();
}
Edited after comment:
Ok, I'm still assuming this is homework, but here are the basics...
I would do this in two phases, data input, then calcualtion.
Create something to store the input in and a counter for the loop
var inputs = new List<double>();
var counter = 0;
Now comes you while loop for your inputs...
while(counter < 100)
{
var tempInput = 0.0D;
Double.TryParse(Console.ReadLine(), out tempInput);
if(tempInput == 0.0D)
{
// The user did not enter something that can be parsed into a double
// If you'd like to use that as the signal that the user is finished entering data,
// just do a break here to exit the loop early
break;
}
inputs.Add(tempInput);
// This is your limiter, once counter reaches 100 the loop will exit on its own
counter++;
}
Now you can just perform the calcualtions on the values you've accumulated...
var total = 0.0D;
foreach(var value in inputs)
{
total += value;
}
Now display the value in total.
Keep in mind there are a multitude of ways to do this this one is just an example to get you past the problem of aquiring the data.

Using the correct loop for incorrect input

I am trying to enter a loop to stop the number of areas being below 0 or above 5, I've tried entering a do while loop, but it still executes the next block of code even when incorrect input has been entered. I've commented the section with the loop. Help would be much appreciated, thank you.
const int MaxItems = 5; // max size of array needed
double[] itemCosts = new double[MaxItems];
int jobType; // valid values are 1=normal, 2=waterproofing, 3=skim
int nAreas;
int i;
string customer;
double totalCost = 0.0;
double averageCost;
const double discountPrice = 800; // price at which discount available
const double discountRate = 0.1; // discount rate
const double setupCostPerArea = 30.00;
// cost of moving furniture, carpets etc.
double discount, discountedTotal; // discount amount and discounted total
double width, height; // width and height of plaster area
double[] basePrices = { 0, 35.0, 30.0, 20.0 }; // added 0 as index placeholder, so 35 can be selected using 1, and so forth.
// prices per square metre for standard, plasterboard and skim, and skim only
Console.Write("enter name of customer: ");
customer = Console.ReadLine();
Console.Write("enter number of plaster areas to quote for: ");
nAreas = Convert.ToInt32(Console.ReadLine());
do
{
Console.WriteLine("Please Enter numbers of rooms between 1 and 5 only!!!!");
} while (nAreas < 1 && nAreas > 5); // loop
for (i = 0; i < nAreas; i++)
{
Console.WriteLine("Data entry for area {0}", i + 1);
Console.Write("enter 1 (standard), 2 (plasterboard and skim) or 3 (skim only): ");
jobType = Convert.ToInt32(Console.ReadLine());
Console.Write("enter width of area {0} in metres: ", i + 1);
width = Convert.ToDouble(Console.ReadLine());
Console.Write("enter height of area {0} in metres: ", i + 1);
height = Convert.ToDouble(Console.ReadLine());
// add base area cost to price based on area and type of plaster
itemCosts[i] = setupCostPerArea + (basePrices[jobType] * (width * height));
totalCost += itemCosts[i];
}
averageCost = totalCost / nAreas;
// main report heading
Console.WriteLine("\n");
Console.WriteLine("Plasterers R US Job Costing Report");
Console.WriteLine("===================================");
Console.WriteLine("\nName of customer: {0}\n", customer);
Console.WriteLine("No. of plaster areas: {0}", nAreas);
Console.WriteLine("Average Cost per area £{0:0.00}", averageCost);
// output subheadings
Console.WriteLine("Area\tCost\tDifference From Average");
for (i = 0; i < nAreas; i++)
{
Console.Write("{0}\t", i + 1);
Console.Write("£{0:0.00}\t", itemCosts[i]);
Console.WriteLine("£{0:0.00}", itemCosts[i] - averageCost);
}
Console.WriteLine("Total Cost £{0:0.00}", totalCost);
if (totalCost > discountPrice)
{
discount = totalCost * discountRate;
discountedTotal = totalCost - discount;
Console.WriteLine(" - Discount of £{0:0.00}", discount);
Console.WriteLine(" Discounted Total £{0:0.00}", discountedTotal);
}
Console.WriteLine("press enter to continue");
Console.ReadLine();
do
{
Console.Write("enter number of plaster areas to quote for: ");
nAreas = Convert.ToInt32(Console.ReadLine());
if(nAreas < 1 || nAreas > 5)
Console.WriteLine("Please Enter numbers of rooms between 1 and 5 only!!!!");
} while (nAreas < 1 || nAreas > 5); // loop
Two problems:
you are not asking for new input within your loop
you have the wrong exit condition for your loop - an illegal are number would be less than 1 or larger than 5.
Adjusting for both:
do
{
Console.Write("enter number of plaster areas to quote for: ");
nAreas = Convert.ToInt32(Console.ReadLine());
if(nAreas < 1 || nAreas > 5)
Console.WriteLine("Please Enter numbers of rooms between 1 and 5 only!!!!");
} while (nAreas < 1 || nAreas > 5); // loop

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