Develop Reference

c# how to fill an array with user input

I'm creating a lottery program that users can choose from a series of numbers between a particular range and the program then creates its own version of numbers and compares those user values against the program's random numbers which any matches that the program then finds are then displayed to the user.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace Assessment1.Lottery
{
internal class Program
{
static void Main(string[] args)
{
Console.WriteLine("Please insert 6 lottery numbers:");
int range = 100;
int minValue = 0;
int maxValue = 100;
int a = 0;
Random rnd = new Random();
int[] myArray = new int[6];
for ( int i=0; i < myArray.Length; i++ )
{
int randomNumber = rnd.Next(minValue, maxValue);
myArray[i] = randomNumber;
Console.WriteLine(randomNumber);
myArray[i] = int.Parse(Console.ReadLine());
Console.WriteLine(myArray[i]);
while (a < 5)
{
if (int.TryParse(Console.ReadLine(), out myArray[a]))
a++;
else
Console.WriteLine("invalid integer");
}
double arry = myArray.Average();
if(arry > 0)
Console.WriteLine("found");
else
Console.WriteLine("not found");
int BinarySearch(int[] array, int value, int low, int high)
{
if ( high >= low)
{
int mid = (low + high) / 2;
if (array[mid] == value) return mid;
if (array[mid] == value) return BinarySearch(array, value, low, mid - 1);
return BinarySearch(array, value, mid + 1, high);
}
return -1;
}
}
Console.ReadLine();
}
}
}
when I run the program it shows the following
Please insert 6 lottery numbers: 64
how can I fix this so that the array can be filled with user input

Here is a version of something I wrote a while back and modified to your parameters, if there are bugs please don't ask me to fix.
static void Main(string[] args)
{
int stop = 0;
int[] chosenNum = new int[6];
while (stop == 0)
{
Console.Clear();
string con = "";
Console.WriteLine("Enter six numbers between 1-100 separated by a comma with no duplicates:");
string numbers = Console.ReadLine();
string[] userNumbers = numbers.Replace(" ", "").Split(new string[] { "," }, StringSplitOptions.RemoveEmptyEntries).ToArray();;//remove ex: ,, issues
string[] checkDup = userNumbers.Distinct().ToArray();//remove duplicates
if (userNumbers.Count() < 6)
{
Console.WriteLine("You entered less than six numbers");
Console.WriteLine("Try Again Y or N");
con = Console.ReadLine();
if (con.ToUpper() != "Y")
{
stop = 1;
}
}
else if (userNumbers.Count() > 6)
{
Console.WriteLine("You entered more than 6 numbers");
Console.WriteLine("Try Again Y or N");
con = Console.ReadLine();
if (con.ToUpper() != "Y")
{
stop = 1;
}
}
else if (checkDup.Count() < 6)
{
Console.WriteLine("You entered duplicate numbers");
Console.WriteLine("Try Again Y or N");
con = Console.ReadLine();
if (con.ToUpper() != "Y")
{
stop = 1;
}
}
else if (!isNumeric(userNumbers))
{
Console.WriteLine("You entered non-numeric value(s)");
Console.WriteLine("Try Again Y or N");
con = Console.ReadLine();
if (con.ToUpper() != "Y")
{
stop = 1;
}
}
else if (isInRange(userNumbers) < 6)
{
Console.WriteLine("You entered out of range value(s)");
Console.WriteLine("Try Again Y or N");
con = Console.ReadLine();
if (con.ToUpper() != "Y")
{
stop = 1;
}
}
else
{
var lowerBound = 1;
var upperBound = 100;
var random = new Random();
int[] randomNum = new int[6];
int count = 0;
foreach(string str in userNumbers){
var rNum = random.Next(lowerBound, upperBound);
randomNum[count] = rNum;
count++;
}
string[] ourPicks = Array.ConvertAll(randomNum, s => s.ToString()).ToArray();
Array.Sort(userNumbers);
Array.Sort(ourPicks);
//string[] ourpicks = { "1", "2" };//for testing
Console.WriteLine("Your Numbers: {0}", string.Join(", ", userNumbers));
Console.WriteLine("Our Numbers: {0}", string.Join(", ", ourPicks));
string[] result = userNumbers.Intersect(ourPicks).ToArray();
if(result.Count() > 0)
{
Console.WriteLine("Matchs: {0}", string.Join(", ", result));
}
else
{
Console.WriteLine("Match's = 0");
}
stop = 1;
}
}
Console.ReadLine();
}
public static bool isNumeric(string[] num)
{
foreach (string str in num)
{
bool check = int.TryParse(str, out int test);
if (!check)
{
return false;
}
}
return true;
}
public static int isInRange(string[] num)
{
int count = 0;
foreach (string str in num)
{
int.TryParse(str, out int test);
if (test > 0 & test <= 100)
{
count++;
}
}
return count;
}

c# subtract a number from an array index in a for loop

I need to find the difference of each number value in an array from an average value. I need to loop through each value and subtract each value FROM the average and display the difference. I have tried several different ways but the difference always comes out as 0 at the end. What am i doing wrong here?
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using static System.Console;
namespace AvgNDiff
{
class Program
{
static void Main(string[] args)
{
int[] numbers = new int[10];
int x = 0;
int i;
string entryString = "";
int counter = 0;
int countdown = 10;
int sum = 0;
int average = 0;
while (counter < numbers.Length && numbers[x] != 10 && entryString != "0")
{
if (x == 0)
Write("Enter up to 10 numbers or type 0 to stop > ");
else if (x == 9)
Write("Enter {0} more number or type 0 to stop > ", countdown);
else
Write("Enter up to {0} more numbers or type 0 to stop > ", countdown);
entryString = ReadLine();
numbers[x] = Convert.ToInt32(entryString);
if (entryString != "0")
{
sum += numbers[x];
counter++;
x++;
}
countdown--;
}
average = sum / x;
WriteLine("\n\nYou entered {0} numbers with a sum of {1}", x, sum);
WriteLine("The average of your numbers is " + average);
WriteLine("\n\nNumber Difference");
WriteLine("-------------------------------");
for (i=0; i < x; i++)
{
int value = numbers[i];
int diff = average-value;
WriteLine(String.Format("{0,-10} {1,-10}", (numbers[i]), diff));
}
ReadKey();
}
}
}

Take a look here
int value = numbers[i];
int diff = value - average;
WriteLine(String.Format("{0,-10} {1,-10}", (numbers[i]), value));
the key issue here is the writeline statement.
Youve told it to display numbers[i], and oh wait.. numbers[i] (as thats what value is)
yet diff contains the variance from the average...

static void Main(string[] args)
{
List<int> numberList = new List<int>();
Console.WriteLine("Enter up to 10 numbers or type 0 to stop:");
for (int i = 0; i < 10; i++)
{
int userInput = 0;
while (!int.TryParse(Console.ReadLine(), out userInput))
{
Console.WriteLine("Only integer numbers accepted, let's try again...:");
}
if (userInput == 0)
{
break;
}
else
{
numberList.Add(userInput);
if (i < 9)
{
Console.WriteLine("Yeah, {0} more number{1} to go!", (9 - i), (i == 8 ? "" : "s"));
}
}
}
double average = numberList.Average();
for (int i = 0; i < numberList.Count; i++)
{
Console.WriteLine("#{0}: {1} - {2} = {3}", (i+1), numberList[i], average, (numberList[i] - average));
}
Console.ReadLine();
}

Do not cram the entire soultion into the single Main, extract (and debug) a method:
// Subtract each item from the average
private static double[] MyNormalize(int[] source) {
double sum = 0.0;
foreach (var item in source)
sum += item;
double[] result = new double[source.Length];
for (int i = 0; i < source.Length; ++i)
result[i] = sum / source.Length - source[i];
return result;
}
...
static void Main(string[] args) {
int[] numbers = new int[10];
...
// Input
while (counter < numbers.Length && numbers[x] != 10 && entryString != "0") {
...
entryString = ReadLine();
numbers[x] = Convert.ToInt32(entryString);
}
// Business logic
double[] norm = MyNormalize(numbers);
// Output
for (int i = 0; i < numbers.Length; ++i)
WriteLine(String.Format("{0,-10} {1,-10}", numbers[i], norm[i]));
}

When I ref bubble sort method and try to print only gives one value?

I am fetching the Grade of the Students. I am trying to fetch Student Grades in sorted order. But when i printed the testgrade variable its just showing only one record at the end.
namespace EX4_GradesMethod
{
class Program
{
static void Main(string[] args)
{
int namelength;
string names;
double grade, max, min, testgradeaverage;
Console.WriteLine("Please enter the amount of names you wish to enter: ");
namelength = Convert.ToInt32(Console.ReadLine());
string[] name = new string[namelength];
double[] testgrades = new double[namelength];
for (int i = 0; i < testgrades.Length; i++)
{
Console.WriteLine("Please enter the names of each student");
names = Convert.ToString(Console.ReadLine());
name[i] += names;
}
for (int i = 0; i < name.Length; i++)
{
Console.WriteLine("Please enter the final grade for " + name[i]);
grade = Convert.ToDouble(Console.ReadLine());
testgrades[i] += grade;
}
max = testgrades.Max();
min = testgrades.Min();
testgradeaverage = testgrades.Average();
Console.WriteLine("The highest grade is: " + max);
Console.WriteLine("The Lowest Grade is:" + min);
Console.WriteLine("The class average is: " + testgradeaverage);
for ( int k = 0; k < namelength - namelength + 1; k++)
{
Console.WriteLine(testgrades[k]);
}
Console.ReadLine();
}
public static void sorted(ref double [] testgrades)
{
double temp = 0;
for (int write = 0; write < testgrades .Length; write++)
{
for (int sort = 0; sort < testgrades.Length - 1; sort++)
{
if (testgrades [sort] > testgrades [sort + 1])
{
temp = testgrades[sort + 1];
testgrades [sort + 1] = testgrades [sort];
testgrades [sort] = temp;
}
}
}
}
}
}

C# mastermind game

In the Main method, in the for loop, if you copy/paste/run whole program in visual, you'll see that i'm trying to end the game. First "if", if the user hasn't guessed; then attempts decrements by one and keeps guessing. The second "else if", if the user has guessed the PCArray, than the game ends and message shows. those work.
But, the first "else if", if the user has exhausted his attempts to guess, and hasn't guessed PCArray, than it should say "oh no, you couldn't guess..." Why is this not working.
I just want it to work so that if:
- user hasn't guessed but still has attempts, attempts decrements by 1 until 0.
- user has guessed the correct number, it says congrats.
- attempts are 0 and user still hasn't guessed number, then show "oh no..." message.
class Program
{
static void Main(string[] args)
{
string name;
Console.WriteLine("**************Let's play Master-Mined**************");
Console.WriteLine();
Console.Write("Please enter your name: ");
name = Console.ReadLine();
Console.WriteLine("Welcome {0}. Have fun!! ", name);
int numberCount = 0;
int difficultyLevel = 0;
int digitNumber = GetRandomNumberCount(numberCount);
Console.Write(digitNumber + " it is. Let's play.");
Console.WriteLine();
int[] PCArray = GenerateRandomNumbers(digitNumber);
Console.WriteLine("A " + digitNumber + "-digit number has been chosen. Each possible digit may be the number 1, 2, 3 or 4.");
Console.WriteLine(" ******");
int difficulty = GetGameDifficulty(difficultyLevel);
int attempts = difficulty * digitNumber;
Console.WriteLine("Enter your guess ({0} guesses remaining)", attempts);
int remaining = attempts;
for (int i = 0; i < attempts; i++)
{
int[] userArray = GetUserGuess(digitNumber);
int hits = CountHits(PCArray, userArray, attempts);
if ((hits != PCArray.Length) && (attempts > 0))
{
remaining--;
Console.WriteLine("Enter your guess ({0} guesses remaining)", remaining);
}
else if ((attempts < 1))
{
Console.WriteLine("Oh no {0}! You couldn't guess the right number.", name);
Console.WriteLine("The correct number is: ");
for (int j = 0; j < PCArray.Length; j++)
{
Console.Write(PCArray[j] + " ");
}
Console.WriteLine("Would you like to play again (Y/N)? ");
}
else if (hits == PCArray.Length)
{
attempts = 0;
Console.WriteLine("You win {0}!", name);
Console.WriteLine("The correct number is:");
for (int j = 0; j < PCArray.Length; j++)
{
Console.Write(PCArray[j] + " ");
}
}
}
Console.ReadLine();
}
public static int GetRandomNumberCount(int numberCount)
{
int number = 0;
do
{
try
{
Console.Write("How many numbers would you like to use in playing the game (4-10)? ");
number = int.Parse(Console.ReadLine());
Console.WriteLine();
}
catch
{
Console.WriteLine("You must pick a number between 4 and 10. Choose again.");
Console.WriteLine();
}
} while ((number < 4) || (number > 10));
return number;
}
public static int GetGameDifficulty(int difficultyLevel)
{
int difficulty = 0;
do
{
try
{
Console.Write("Choose a difficulty level (1=hard, 2=medium, 3=easy): ");
difficulty = int.Parse(Console.ReadLine());
}
catch
{
Console.WriteLine(" Incorrect entry: Please re-enter.");
}
} while ((difficulty < 1) || (difficulty > 3));
return difficulty;
}
public static int[] GenerateRandomNumbers(int PCSize)
{
int eachNumber;
int[] randomNumber = new int[PCSize];
Random rnd = new Random();
for (int i = 0; i < randomNumber.Length; i++)
{
eachNumber = rnd.Next(1, 5);
randomNumber[i] = eachNumber;
Console.Write(eachNumber);
}
Console.WriteLine();
return randomNumber;
}
public static int[] GetUserGuess(int userSize)
{
int number = 0;
int[] userGuess = new int[userSize];
for (int i = 0; i < userGuess.Length; i++)
{
Console.Write("Digit {0}: ", (i + 1));
number = int.Parse(Console.ReadLine());
userGuess[i] = number;
//Console.Write(number);
}
Console.WriteLine();
Console.Write("Your guess: ");
for (int i = 0; i < userGuess.Length; i++)
{
Console.Write(userGuess[i] + " ");
}
Console.WriteLine();
return userGuess;
}
public static int CountHits(int[] PCArray, int[] userArray, int attempts)
{
int hit = 0;
int miss = 0;
int hits = 0;
for (int i = 0; i < PCArray.Length; i++)
{
if (PCArray[i] == userArray[i])
{
hit = hit + 1;
hits = hit;
}
else
{
miss = miss + 1;
}
}
Console.WriteLine("Results: {0} Hit(s), {1} Miss(es)", hit, miss);
return hits;
}
}

First of all, you should rethink your code, because the flow control is scattered throughout your code. For example, you don't need both attempts and remaining, they control the same thing.
Using two variables to control the same thing is what is causing your problem. The first two ifs in your for should be like this:
if (hits != PCArray.Length && remaining > 1)
and
else if (remaining == 1)
Note I removed the unnecessary parenthesis. With these changes, your application works, although the code is not too pretty.
A simple way of enhancing your code is to first check for the right result, and if it's not, then decrease the attempts variable and finally check for its value. That's why with your code as it is, the if should compare to 1 instead of 0.
The hits variable in your CountHits method is totally unnecessary; you should just return hit. Actually the miss variable can be avoided too, you can calculate it. Also remember to use the ++ operator.
But as I said first, the important thing is not to make it work but to organize your code properly. Later I will post my version.
My version, it's not the most beautiful thing in the world but I didn't want to change much of your code structure:
class Program
{
static void Main(string[] args)
{
Console.WriteLine("************** Let's play Master-Mind **************\n");
string name = GetPlayerName();
do
{
Play(name);
Console.Write("\nWould you like to play again (Y/N)? ");
}
while (Console.ReadLine().ToUpper() == "Y");
}
private static void Play(string name)
{
int numberCount = GetRandomNumberCount();
Console.Write(numberCount + " it is. Let's play.");
Console.WriteLine();
int[] PCArray = GenerateRandomNumbers(numberCount);
Console.WriteLine("A {0}-digit number has been chosen. Each possible digit may be the number 1 to 4.\n", numberCount);
int difficulty = GetGameDifficulty();
bool won = false;
for (int allowedAttempts = difficulty * numberCount; allowedAttempts > 0 && !won; allowedAttempts--)
{
Console.WriteLine("\nEnter your guess ({0} guesses remaining)", allowedAttempts);
int[] userArray = GetUserGuess(numberCount);
if (CountHits(PCArray, userArray) == numberCount)
won = true;
}
if (won)
Console.WriteLine("You win, {0}!", name);
else
Console.WriteLine("Oh no, {0}! You couldn't guess the right number.", name);
Console.Write("The correct number is: ");
for (int j = 0; j < numberCount; j++)
Console.Write(PCArray[j] + " ");
Console.WriteLine();
}
private static string GetPlayerName()
{
Console.Write("Please enter your name: ");
string name = Console.ReadLine();
Console.WriteLine("Welcome, {0}. Have fun!!\n", name);
return name;
}
public static int GetRandomNumberCount()
{
int number;
Console.Write("How many numbers would you like to use in playing the game (4-10)? ");
while (!int.TryParse(Console.ReadLine(), out number) || number < 4 || number > 10)
Console.WriteLine("You must pick a number between 4 and 10. Choose again.");
return number;
}
public static int GetGameDifficulty()
{
int difficulty = 0;
Console.Write("Choose a difficulty level (1=hard, 2=medium, 3=easy): ");
while (!int.TryParse(Console.ReadLine(), out difficulty) || difficulty < 1 || difficulty > 3)
Console.WriteLine("Incorrect entry: Please re-enter.");
return difficulty;
}
public static int[] GenerateRandomNumbers(int PCSize)
{
int eachNumber;
int[] randomNumber = new int[PCSize];
Random rnd = new Random();
Console.Write("PC number: ");
for (int i = 0; i < PCSize; i++)
{
eachNumber = rnd.Next(1, 5);
randomNumber[i] = eachNumber;
Console.Write(eachNumber);
}
Console.WriteLine();
return randomNumber;
}
public static int[] GetUserGuess(int userSize)
{
int number = 0;
int[] userGuess = new int[userSize];
for (int i = 0; i < userSize; i++)
{
Console.Write("Digit {0}: ", (i + 1));
while (!int.TryParse(Console.ReadLine(), out number) || number < 1 || number > 4)
Console.WriteLine("Invalid number!");
userGuess[i] = number;
}
Console.WriteLine();
Console.Write("Your guess: ");
for (int i = 0; i < userSize; i++)
{
Console.Write(userGuess[i] + " ");
}
Console.WriteLine();
return userGuess;
}
public static int CountHits(int[] PCArray, int[] userArray)
{
int hits = 0;
for (int i = 0; i < PCArray.Length; i++)
{
if (PCArray[i] == userArray[i])
hits++;
}
Console.WriteLine("Results: {0} Hit(s), {1} Miss(es)", hits, PCArray.Length - hits);
return hits;
}
}
It does a few more validations and it even actually lets you play again! ;)

Number of zeroes at the end of factorial

I need to find the number of zeroes at the end of a factorial number. So here is my code, but it doesn't quite work :/
using System;
class Sum
{
static void Main(string[] args)
{
int n = int.Parse(Console.ReadLine());
long factoriel = 1;
for (int i = 1; i <= n; i++)
{
factoriel *= i;
}
Console.WriteLine(factoriel);
int timesZero = 0;
while(factoriel % 10 != 0)
{
timesZero++;
}
Console.WriteLine(timesZero);
}
}
I know I can use a for loop and divide by 5, but I don't want to. Where is the problem in my code and why isn't it working?

There's problem with your algorithm: integer overflow. Imagine, that you are given
n = 1000
and so n! = 4.0238...e2567; you should not compute n! but count its terms that are in form of (5**p)*m where p and m are some integers:
5 * m gives you one zero
25 * m gives you two zeros
625 * m gives you three zeros etc
The simplest code (which is slow on big n) is
static void Main(string[] args) {
...
int timesZero = 0;
for (int i = 5; i <= n; i += 5) {
int term = i;
while ((term % 5) == 0) {
timesZero += 1;
term /= 5;
}
}
...
}
Much faster implementation is
static void Main(string[] args) {
...
int timesZero = 0;
for (int power5 = 5; power5 <= n; power5 *= 5)
timesZero += n / power5;
...
}

Counting Trailing zeros in Factorial
static int countZerosInFactOf(int n)##
{
int result = 0;
int start = 1;
while (n >= start)
{
start *= 5;
result += (int)n/start;
}
return result;
}

Make sure to add inbuilt Reference System.Numeric
using System.Text;
using System.Threading.Tasks;
using System.Numeric
namespace TrailingZeroFromFact
{
class Program
{
static void Main(string[] args)
{
Console.WriteLine("Enter a no");
int no = int.Parse(Console.ReadLine());
BigInterger fact = 1;
if (no > 0)
{
for (int i = 1; i <= no; i++)
{
fact = fact * i;
}
Console.WriteLine("{0}!={1}", no, fact);
string str = fact.ToString();
string[] ss = str.Split('0');
int count = 0;
for (int i = ss.Length - 1; i >= 0; i--)
{
if (ss[i] == "")
count = count + 1;
else
break;
}
Console.WriteLine("No of trailing zeroes are = {0}", count);
}
else
{
Console.WriteLine("Can't calculate factorial of negative no");
}
Console.ReadKey();
}
}
}

static void Main(string[] args)
{
Console.WriteLine("Enter the number:");
int n = int.Parse(Console.ReadLine());
int zero = 0;
long fac=1;
for (int i = 1; i <= n; i++)
{
fac *= i;
}
Console.WriteLine("Factorial is:" + fac);
ab:
if (fac % 10 == 0)
{
fac = fac / 10;
zero++;
goto ab;
}
else
{
Console.WriteLine("Zeros are:" + zero);
}
Console.ReadLine();
}

Your code seems fine, just a little correction in the while-condition:
public static int CalculateTrailingZeroes(BigInteger bigNum)
{
int zeroesCounter = 0;
while (bigNum % 10 == 0)
{
zeroesCounter++;
bigNum /=10;
}
return zeroesCounter;
}
That works, I just tested it.