如何检查数组中的副本?

How do I store a random number into my array, but only if there is not a duplicate already inside the array? My code below still inputs a duplicate number.

如何在数组中存储一个随机数，但前提是数组中已经没有副本了?我下面的代码仍然输入一个重复的数字。

        Random rand = new Random();
        int[] lotto = new int [6];

        for (int i = 0; i < lotto.Length; i++)
        {
            int temp = rand.Next(1, 10);
            while (!(lotto.Contains(temp)))//While my lotto array doesn't contain a duplicate
            {
                lotto[i] = rand.Next(1, 10);//Add a new number into the array
            }
            Console.WriteLine(lotto[i]+1);
        }

2 个解决方案

#1

Try this:

试试这个:

Random rand = new Random();
int[] lotto = new int[6];

for (int i = 0; i < lotto.Length; i++)
{
    int temp = rand.Next(1, 10);

    // Loop until array doesn't contain temp
    while (lotto.Contains(temp))
    {
        temp = rand.Next(1, 10);
    }

    lotto[i] = temp;
    Console.WriteLine(lotto[i] + 1);
}

This way the code keeps generating a number until it finds one that isn't in the array, assigns it and moves on.

这样，代码就会一直生成一个数字，直到找到一个不在数组中的数字，分配它，然后继续。

There are a lot of ways to 'shuffle' an array, but hopefully this clears up the issue you were having with your code.

有很多方法可以“洗牌”数组，但希望这能解决您在代码中遇到的问题。

#2

What you really want is to shuffle the numbers from 1 to 9 (at least that's what your example is implying) and then take the first 6 elements. Checking for duplicates is adding unnecessary indeterminism and really is not needed if you have a shuffle.

你真正想要的是把数字从1到9(至少是你的例子所暗示的)，然后取前6个元素。检查重复是否增加了不必要的不确定性，如果你进行了洗牌，实际上是不需要的。

E.g take this accepted answer for a Fisher-Yates shuffle and then take the first 6 elements for lotto.

E。g接受这个公认的答案，对鱼-耶茨洗牌，然后取第6个元素的乐透。

This would then look like this:

这个看起来是这样的:

lotto = Enumerable.Range(1,9)
                  .Shuffle()
                  .Take(6)
                  .ToArray();

#1