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C#: Generate 100 random numbers between 1-1000 and output the max value

I'm very new to coding and I just can't wrap my head around Loops/Arrays/Randoms. I understand the concept but when it comes to applying it, I'm just lost.
Here I'm trying to generate 100 random numbers between 1-1000 and it has to output the maximum value. Here's my code so far:
Random rnd = new Random();
int nums = rnd.Next(0, 1001);
for (int i = 1; i <= 100; i++)
{
}
Console.WriteLine(nums);
Console.ReadLine();
It's only giving me one number. :(
I'd greatly appreciate any help!
Thanks!

You can accumulate your random generated number to the array and then by using Max function of the array you can find the maximum value
class Program
{
public static void Main(string[] args)
{
Random rnd = new Random();
int[] intArr = new int[100];
for (int i = 0; i < intArr.Length; i++)
{
int num = rnd.Next(1, 1000);
intArr[i] = num;
Console.WriteLine(num);
}
Console.WriteLine();
int maxNum = intArr.Max();
Console.WriteLine("The max num is:" + maxNum);
Console.ReadLine();
}
}
Click to watch online demo

You need to call rnd.Next() inside loop.
Random rnd = new Random();
for (int i = 1; i <= 100; i++)
{
int nums = rnd.Next(0, 1001);
Console.WriteLine(nums);
}
Console.ReadLine();

A good approach would be initializing a variable that stores your max. Then generate a random number within your iterative block and if it is greater than your max, set it as the new max.
Random r = new Random();
int max = 0; //declare our max variable
for(int i = 0; i < 100; i++)
{
int rand = r.Next(0, 1001);
if(rand > max) //if the new random value is greater than our max, set max = rand
max = rand;
}
Console.WriteLine(max); //Output the maximum value
Console.ReadLine();
If you want to output every random value and then output the max out of all the values generated, simply modify the code above by outputting rand within your loop as well.
Hope this helps!

I am not sure, are you asking like this?
Random random = new Random();
int[] nums = new int[100];
// when for loop ends, nums are full of 100 numbers
for (int i = 0; i < nums.Length; i++)
{
int newNum = random.Next(1, 1000);
// show every number
Console.WriteLine(newNum);
nums[i] = newNum;
}
// get the max number
var maxNum = nums.Max();
Console.WriteLine(maxNum);

If you want to see the code for Loops/Arrays/Randoms all working together you can use the below with the comments walking through what each line is doing (Working .NET Fiddle Example)
public static void Main()
{
// Pass in what range we want our randomly generated numbers to be in
// In your case, between 1 - 1000 and we want to create 100 of them.
//(See GenerateRandomNumbers())
var random = GenerateRandomNumbers(1, 1000, 100);
//Take our newly returned randomly created numbers and
//pass them to our GetMaxNumber method so it can find the Max number
//See (GetMaxNumber())
var result = GetMaxNumber(random);
//We now have our max number; print it to the Console.
Console.WriteLine("Max: " + result);
}
public static int GetMaxNumber(params int[] inputs)
{
//Create a variable that will store the largest number we find in our array
int max = inputs[0];
//Iterate (loop) through all of the 100 values in our array that we passed in
//Here we define "input" which will hold the value for each value in inputs as we check
//if the value of input is greater than our current value of max. If it is greater than our
//current value of max, then we need to update max to now be equal to the value of our input.
//Note: it will do this comparison 100 times beginning with the first value in the inputs array
foreach (var input in inputs)
{
if (input > max)
{
//input's value is greater than the current value of max; update max so that it is equal to the current value of input.
max = input;
}
//no more code; return to top of foreach loop and set input to the next value in inputs
}
//When we get here, it means our foreach loop has completed going through and comparing all 100 values of inputs to see which value is the largest.
//now return this value to Main()
return max;
}
public static int[] GenerateRandomNumbers(int beginRange, int endRange, int maxNumbers)
{
// Instantiate random number generator
Random rnd = new Random();
//Generate and display
int[] intArr = new int[maxNumbers];
//Generate 100 numbers with numbers between 1 and 1000
for (int i = 0; i < intArr.Length; i++)
{
int num = rnd.Next(beginRange, endRange);
intArr[i] = num;
}
return intArr;
}

The biggest value in array and check if all elements in array have equal values. (C#)

I'm working on a project. The user inputs a value(n) and that value is multiplied by 2. Then the user inputs the exact same times a new number (n*2). So I have to figure out if every couple of numbers are equal and if not to print the biggest difference between one of the couples. In order to do that I need Biggest value in an array and somehow to check if all elements in an array are equal. I'm new to C# and I don't know much about arrays.(btw sorry about the use of language, I'm foreigner)
I came up with this code so far:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace EqualPairs
{
class Program
{
static void Main(string[] args)
{
int n = int.Parse(Console.ReadLine());
int sum = 0;
int diff = 0;
int[] sumAll = new int[n];
int[] differ = new int[n];
for (int i = 1; i <= n; i++)
{
sum = 0;
diff = 0;
for (int j = 1; j <= 2; j++)
{
int number = int.Parse(Console.ReadLine());
sum = sum + number;
diff = Math.Abs(diff - number);
}
sumAll[i - 1] = sum;
differ[i - 1] = diff;
}
}
}
}

I'm not sure exactly what you're trying to do with your program, but to answer your questions:
Find max value in an array:
int maxValue = yourArray.Max();
Check if all values in your array are equal (using System.Linq):
int first = yourArray.First();
bool allElementsEqual = yourArray.All(x => x == first);
Edit based on OP's comment:
If I were you, I'd create an intermediate array couplesArray. Not sure how you're planning to set up your inputs and all that, but I'm assuming yourArray has an even number of values. I don't know how you're defining max difference and all that, so perhaps drop some of my Math.Abs() calls:
int[] yourArray = { 1, 2, 0, 3, 4, -1};
int[] couplesArray = new int[yourArray.Count() / 2];
for (int i = 0; i < couplesArray.Length; i++)
{
couplesArray[i] = yourArray[2 * i] + yourArray[2 * i + 1];
}
int first = couplesArray.First();
bool allElementsEqual = couplesArray.All(x => x == first);
int maxDifference = Math.Max(Math.Abs(couplesArray.Max()), Math.Abs(couplesArray.Min()));
string outputString = allElementsEqual ? "Equal" : maxDifference.ToString();
Console.WriteLine(outputString);

get max odd number

class Program
{
static void Main(string[] args)
{
Random rnd = new Random();
int[] mass = new int[10];
for (int i = 0; i < mass.Length; i++)
{
mass[i] = rnd.Next(0, 10);
}
Console.WriteLine("display random Massive: \n");
foreach (var i in mass)
{
Console.Write("{0} ", i);
}
Console.WriteLine("\n");
int max = mass.Max();
Console.WriteLine("max value in Massive = {0}", max);
Console.ReadLine();
}
}
my code gives me max value in massive, I need get max odd value. How to get max odd value?

You can use Linq to do this easily
mass.Where (x => x % 2 != 0).Max ();

You can do this easier using linq:
static void Main(string[] args)
{
Random rnd = new Random();
int[] mass = Enumerable.Range(0, 10).Select(i => rnd.Next(0, 10)).ToArray();
Console.WriteLine("display random Massive: ");
Console.WriteLine(string.Join(" ", mass));
Console.WriteLine();
int max = mass.Where(i => (i & 1) == 1).Max();
Console.WriteLine("max value in Massive = {0}", max);
Console.ReadLine();
}
Explanations:
I initialize the array by generating 10 random numbers, converting them to an array
I output them using string.Join
using Where with testing that the last bit is set filters for odd numbers
calling Max on only these odd numbers.
Note that you don't need to use \n as Console.WriteLine adds a new line at the end.

just change
int max = mass.Max();
to
int max = mass.Where(x=>(x%2)==1).Max();

I am asuming you're a beginner like me and don't understand linq yet
Declare a list for holding odd values
List<int> oddList = new List<int>();
Then in your foreach method
foreach (var i in mass)
{
if (i % 2 != 0) //check that number is odd
{
oddList.Add(i); //add odd randoms to list
{
}
Console. WriteLine(oddList.Max().ToString());

Total sum/average of random numbers in c#

I am new to programming and i would be delighted if someone could help me with the following question: "Write a program that randomly selects integers whose values range from 0 to 9. The program will calculate the average of the random numbers and print how many of the random numbers are larger than the average. The program's user will specify how many numbers will be randomly generated". How do you get the total sum of random numbers so you can get the average? This is what i got so far:
int ChosenRandom;
Console.Write("Choose a number between 0-10; ");
ChosenRandom = int.Parse(Console.ReadLine());
Random rnd = new Random();
int RandomNumber = rnd.Next(0, 10);
for (int i = 0; i < ChosenRandom; i++)
{
Console.WriteLine("Random numbers: " + rnd.Next(0, 10));
}
int TotalRandom;
TotalRandom = ChosenRandom + (RandomNumber);
Console.WriteLine("Total is:" + TotalRandom);
int avr;
avr = TotalRandom / ChosenRandom;
Console.WriteLine("Average is: " + avr);
if (ChosenRandom > avr)
{
Console.WriteLine("Numbers larger than average" + ChosenRandom);
}
else
{
Console.WriteLine("All numbers under average");
}

simplest way is by using arrays,
store the numbers in an array while generating them
use the array elements to find the total and average
traverse through array comparing each element with that of average

Check if this solution helps for you.
I have used linq to create average and find all numbers above the 'average'.
using System;
using System.Linq;
namespace Test
{
class Program
{
static void Main()
{
int chosenRandom;
Console.WriteLine("Choose a number between 0-10");
chosenRandom = int.Parse(Console.ReadLine());
Random rand = new Random();
double[] randomNumbers = new double[chosenRandom];
for(int i = 0; i < chosenRandom; i++)
{
Console.WriteLine("Random numbers: " + (randomNumbers[i] = rand.Next(0, 10)));
}
double average = randomNumbers.Average(t => t);
var numbersAboveAverage = randomNumbers.Where(t => t > average);
Console.WriteLine("Average of all random numbers - {0}", average);
foreach(var number in numbersAboveAverage)
Console.WriteLine(number);
}
}
}

Your program looks good. But, you understood the question in a wrong way! The question says that the value of random integers should be 0-9. Not the no of random numbers. The number of random numbers can be of any value as given by user.
Please find below the complete implementation.
class Program
{
static void Main(string[] args)
{
//Step 1. Get the no of random numbers (n) to be generated from user.
Console.WriteLine("Enter the no of Random numbers: ");
int n = int.Parse(Console.ReadLine());
//Step 2. Generate 'n' no of random numbers with values rangeing from 0 to 9 and save them in an array.
Random rand = new Random();
int[] randCollection = new int[n];
for (int i = 0; i < n; i++)
{
randCollection[i] = rand.Next(9);
Console.WriteLine("Random No {0} = {1}", i + 1, randCollection[i]);
}
//Step 3. Compute Average
double average = randCollection.Average();
Console.WriteLine("Average = {0}", average);
//Step 4. Find out how many numbers in the array are greated than the average.
int count = 0;
foreach(int i in randCollection){
if (i > average) count++;
}
Console.WriteLine("No of random numbers above their average = {0}", count);
Console.ReadLine();
}
}
Hope this helps. Let me know if you have any questions.

Adding Array Elements

i'm attempting to learn C# and I have this code. I want it to display a random list of integers and then add them all together within the array and then display the average of all the numbers. Where have I gone wrong, can anyone help? Thanks.
using System;
class grades
{
public static void Main(string[] args)
{
int sumValue = 0;
int[] grades = new int [ 30 ];
Random rnd = new Random();
for (int i = 0; i < 30; i++)
grades[i] = rnd.Next(1,101);
foreach (int i in grades)
{
Console.WriteLine("{0}", i);
sumValue = sumValue + i;
}
double average = sumValue/30;
Console.WriteLine("{0}", average);
}
}

Yeah, the random integers are displayed but the adding and the average isn't calculated.
Yes, it is; you can make it more obvious:
double average = sumValue / 30.0;
Console.WriteLine("The average is: {0:##0.0}", average);
Note also the .0 which ensures we aren't doing integer arithmetic (different fraction / rounding rules).