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Write a program that reads N and then continuously read integers and check if there are odd or even until odd and even number equals N

This is what I tried:
using System;
namespace OddAndEvenNumbers
{
class Program
{
static void Main(string[] args)
{
int requiredOddAndEvenNumbers = Convert.ToInt32(Console.ReadLine());
int oddNumbersCount = 0;
int evenNumbersCount = 0;
int n = Convert.ToInt32(Console.ReadLine());
while (oddNumbersCount <= requiredOddAndEvenNumbers || evenNumbersCount <= requiredOddAndEvenNumbers)
{
if (n % 2 == 0)
{
evenNumbersCount++;
}
else if (n % 2 != 0)
{
oddNumbersCount++;
}
}
Console.WriteLine(evenNumbersCount + " " + oddNumbersCount);
Console.ReadLine();
}
}
}
I don't know why it doesn't work.
The program should stop when odd numbers and even number equals N.

You never update n so the loop will never exit
So evenNumbersCount and oddNumbersCount will never count up
using System;
namespace OddAndEvenNumbers
{
class Program
{
static void Main(string[] args)
{
int requiredOddAndEvenNumbers = Convert.ToInt32(Console.ReadLine());
int oddNumbersCount = 0;
int evenNumbersCount = 0;
int n = Convert.ToInt32(Console.ReadLine());
while (oddNumbersCount <= requiredOddAndEvenNumbers || evenNumbersCount <= requiredOddAndEvenNumbers)
{
if (n % 2 == 0)
{
evenNumbersCount++;
}
else if (n % 2 != 0)
{
oddNumbersCount++;
}
n++;
}
Console.WriteLine(evenNumbersCount + " " + oddNumbersCount);
Console.ReadLine();
}
}
}

It seems you've forgotten to get new number inside the loop. It keeps checking the first number
ItThe while loop works until the Odd + Even numbers are equal to n.
int requiredOddAndEvenNumbers = Convert.ToInt32(Console.ReadLine());
int oddNumbersCount = 0;
int evenNumbersCount = 0;
int n = 0;
while ((oddNumbersCount + evenNumbersCount) < requiredOddAndEvenNumbers)
{
n = Convert.ToInt32(Console.ReadLine());
if (n % 2 == 0)
{
evenNumbersCount++;
}
else if (n % 2 != 0)
{
oddNumbersCount++;
}
}
Console.WriteLine("evenNumbersCount: {0}", evenNumbersCount);
Console.WriteLine("oddNumbersCount: {0}", oddNumbersCount);

Prime Number Verifier Code Blocks resturns me converting problems in C#

static void Main(string[] args)
{
if (isPrimeNumber(6))
{
Console.WriteLine("This is prime number");
}
else
{
Console.WriteLine("This is not prime number");
}
Console.ReadLine();
}
private static bool isPrimeNumber(int number)
{
bool result = true;
for (int i = 0; number - 1; i++)
{
if (number % i == 0)
{
result = false;
i = number;
}
}
return result;
}
hey! there is a problem in my code blocks about prime number verifying. this program returns me that in for loop: cannot convert type "int" to "bool". how can i fix it? what's my wrong?

for (int i = 0; number - 1; i++) should be for (int i = 0; i < number; i++) The number - 1 is not a boolean expression.
private static bool isPrimeNumber(int number)
{
bool result = true;
for (int i = 2; i < number; i++)
{
if (number % i == 0)
{
result = false;
i = number;
}
}
return result;
}
i fixed it for (int i = 0; i < number; i++) should be for (int i = 2; i < number; i++)

You have logical error, look
//typo: should be i < number - 1 instead of number - 1
for (int i = 0; i < number - 1; i++)
{
if (number % i == 0) // <- always true, when i == 1
{
result = false; // <- result == false whenever number >= 2
i = number;
}
}
whenever i == 1 then number % i == 0 and you have result = false.
Let's implement isPrimeNumber from scratch:
private static bool isPrimeNumber(int number) {
// 0, 1 and negative numbers are not prime
if (number <= 1)
return false;
// we have just one even prime number, it's 2
if (number % 2 == 0)
return number == 2;
// if we have a non-trivial divisors, the minimal one
// is at most Sqrt(number)
// (int) (...+1) - to be on the safe side in case of rounding errors
int maxDivisor = (int)(Math.Sqrt(number) + 1);
// Now we check divisor = 3, 5, 7, ..., maxDivisor
for (int divisor = 3; divisor <= maxDivisor; divisor += 2)
if (number % divisor == 0)
return false;
// All tests passed, number is prime
return true;
}

Is a given number a prime or not, if not output all its divisors

The main part of my code is working, the only thing that doesn't work is the output of all its divisors. My result if it's not a prime should be like this:
Input -> 4
Output -> false 1 2 4
Console.WriteLine("Type your number: ");
int n = Convert.ToInt32(Console.ReadLine());
int a = 0, i;
for (i = 1; i <= n; i++)
{
if (n % i == 0)
{
a++;
}
}
if (a == 2)
{
Console.WriteLine("true");
}
else
{
Console.WriteLine("false" + i);
}
Console.ReadLine();

To print all the divisors, you'll need to gather them up in a collection of some sort – a list of integers, here.
In addition, all integers are divisible by 1, so you don't want to start there; neither do you want to end at n, since n % n == 0.
var divisors = new List<int>();
for (var i = 2; i < 2; i++)
{
if (n % i == 0)
{
divisors.Add(i);
}
}
if (divisors.Count == 0)
{
Console.WriteLine("true");
}
else
{
Console.WriteLine("false " + String.Join(" ", divisors));
}

Here is a working solution. You basically have to store your divisors somewhere or print them directly:
public static void Method(int n)
{
if (IsPrime(n))
{
Console.WriteLine($"{n} is a prime");
return;
}
var divisors = new List<int>();
for(var i = 1; i <= n; i++)
{
if (n % i == 0)
divisors.Add(i);
}
Console.WriteLine($"{n} isn't a prime");
Console.WriteLine($"The divisors are: {string.Join(", ", divisors)}");
}
public static bool IsPrime(int n)
{
for(var i = 2; i < n; i++)
{
if (n % i == 0)
return false;
}
return true;
}

From a brief inspection, there are two ways to generate the output. So far, you count the number of divisors, but neither store them nor write them to the output. You could replace
if (n % i == 0)
{
a++;
}
by
if (n % i == 0)
{
Console.WriteLine(i);
a++;
}
or store the divisors in a
List<int>
to generate the output afterwards.

Console.ReadLine() not exiting Program in c#

I have an assignment where I have to create code to display factors and whether a number is a perfect and/or prime number. I think I have all the code right to run my program, but when I get to the last line (Console.ReadLine()) I expect to hit enter and then exit the program. Currently, when I hit enter, the program displays whether it is a prime number and/or perfect number over and over again (each time you hit enter). So basically, it executes everything after the while loop over and over again.
Keep in mind, I'm very new to C#, so some of my syntax and readability may be weird. I am only interested in answers that will help me solve the ReadLine issue. My instructors will help me with making my code more readable and organized.
Thanks for your advice! Here is my code. I commented where the ReadLine isn't closing the program:
using System;
namespace Factorizer.UI
{
class Program
{
static void Main(string[] args)
{
string input;
int num, i, x = 0, sum = 0;
while (true)
{
Console.Write("Enter a number: ");
input = Console.ReadLine();
if (int.TryParse(input, out num))
{
Console.Write("\nThe factors are: ");
for (i = 1; i <= num; i++)
{
if (num % i == 0)
{
Console.Write("{0} ", i);
}
}
break;
}
else
{
Console.WriteLine("\nThat was not a valid number!\n");
}
}
for (i = 1; i < num; i++)
{
if (num % i == 0)
{
sum = sum + i;
}
if (sum == num)
{
Console.Write("\n\n{0} is a perfect number.\n", num);
}
else
{
Console.Write("\n\n{0} is not a perfect number.\n", num);
}
for (i = 2; i <= num / 2; i++)
{
if (num % i == 0)
{
x++;
break;
}
}
if (x == 0 && num != 1)
{
Console.Write("\n{0} is a prime number.", num);
}
else
{
Console.Write("\n{0} is not a prime number.", num);
}
Console.ReadLine(); //this isn't closing the program!
}
}
}
}

Console.ReadLine() is inside the for loop. Move it down after the next bracket.

Just put Console.ReadLine(); after the for, it's inside the for block that's why it keeps printing and remove the for that you have after the while block, like this:
string input;
int num, i, x = 0, sum = 0;
while (true)
{
Console.Write("Enter a number: ");
input = Console.ReadLine();
if (int.TryParse(input, out num))
{
Console.Write("\nThe factors are: ");
for (i = 1; i <= num; i++)
{
if (num % i == 0)
{
Console.Write("{0} ", i);
}
}
break;
}
else
{
Console.WriteLine("\nThat was not a valid number!\n");
}
}
/*for (i = 1; i < num; i++)
{*/
if (num % i == 0)
{
sum = sum + i;
}
if (sum == num)
{
Console.Write("\n\n{0} is a perfect number.\n", num);
}
else
{
Console.Write("\n\n{0} is not a perfect number.\n", num);
}
for (i = 2; i <= num / 2; i++)
{
if (num % i == 0)
{
x++;
break;
}
}
if (x == 0 && num != 1)
{
Console.Write("\n{0} is a prime number.", num);
}
else
{
Console.Write("\n{0} is not a prime number.", num);
}
Console.ReadLine(); //this isn't closing the program!
//}

C# - Checking for prime numbers in a limit [closed]

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I would like to write a code that shows a list of prime number one number to another number. For example from 1 to 8, it would be 2, 3, 5, 7. I got a code from "Check if number is prime number" by user1954418 because I did not know where to begin, so I take NO credit whatsoever for the code.
int num1;
Console.WriteLine("Prime Number:");
num1 = Convert.ToInt32(Console.ReadLine());
if (num1 == 0 || num1 == 1)
{
Console.WriteLine(num1 + " is not prime number");
Console.ReadLine();
}
else
{
for (int a = 2; a <= num1 / 10; a++)
{
if (num1 % a == 0)
{
Console.WriteLine(num1 + " is not prime number");
return;
}
}
Console.WriteLine(num1 + " is a prime number");
Console.ReadLine();
}

Here is a sample that should work. The code from isPrime I just got from here Here
Then In the main function just have the loop that goes from you starting number to the end number, and runs the isPrime function on each one.
Here is the code:
class Program
{
static void Main(string[] args)
{
int numberStart;
int numberEnd;
// Take in the start point and the end point
Console.WriteLine("Starting Number:");
if(!int.TryParse(Console.ReadLine(), out numberStart)){
Console.WriteLine("Your input is invalid.");
}
Console.WriteLine("Ending Number:");
if (!int.TryParse(Console.ReadLine(), out numberEnd))
{
Console.WriteLine("Your input is invalid.");
}
// Loop from the first number to the last number, and check if each one is prime
for (int number = numberStart; number < numberEnd; number++)
{
Console.WriteLine(number + " is prime?");
Console.WriteLine(isPrime(number) + "\n");
}
Console.ReadLine();
}
// Function for checking if a given number is prime.
public static bool isPrime(int number)
{
int boundary = (int) Math.Floor(Math.Sqrt(number));
if (number == 1) return false;
if (number == 2) return true;
for (int i = 2; i <= boundary; ++i)
{
if (number % i == 0) return false;
}
return true;
}
}
Note that the function isPrime() only checks up to the root, as it is unnecessary to check further as mentioned by the user from the link.
Hope it helps :)

Make it simple; following code will help you:
Console.WriteLine("Enter the Limit:");
int Limit;
if (!int.TryParse(Console.ReadLine(), out Limit))
{
Console.WriteLine("Invalid input");
}
Console.WriteLine("List of prime numbers between 0 and {0} are :",Limit);
for (int i = 2; i < Limit; i++)
{
if (checkForPrime(i))
Console.WriteLine(i);
}
Console.ReadKey();
Where checkForPrime() is defined as follows:
public static bool checkForPrime(int Number)
{
for (int a = 2; a <= Number / 2; a++)
{
if (Number % a == 0)
{
return false;
}
}
return true;
}

Here's some code I wrote/copied to do this in one of my projects. It could probably be a little smoother but it gets the job done.
// Found this awesome code at http://csharphelper.com/blog/2014/08/use-the-sieve-of-eratosthenes-to-find-prime-numbers-in-c/
// This creates a List of Booleans where you can check if a value x is prime by simply doing if(is_prime[x]);
public static bool[] MakeSieve(int max)
{
var sqrt = Math.Sqrt((double)max);
// Make an array indicating whether numbers are prime.
var isPrime = new bool[max + 1];
for (var i = 2; i <= max; i++) isPrime[i] = true;
// Cross out multiples.
for (var i = 2; i <= sqrt; i++)
{
// See if i is prime.
if (!isPrime[i]) continue;
// Knock out multiples of i.
for (var j = i * 2; j <= max; j += i)
isPrime[j] = false;
}
return isPrime;
}
public static List<int> GetListOfPrimes(int max)
{
var isPrime = MakeSieve(max);
return new List<int>(Enumerable.Range(1, max).Where(x => isPrime[x]));
//var returnList = new List<int>();
//for (int i = 0; i <= max; i++) if (isPrime[i]) returnList.Add(i);
//return returnList;
}
Here's an example of usage:
static void Main(string[] args)
{
var x = GetListOfPrimes(8);
foreach (var y in x)
{
Console.WriteLine(y);
}
Console.Read();
}