unity 随机数不重复

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class RandmR : MonoBehaviour
{

    private int[] testArray;
    private int total;
    private int count;
    private int[] sequence;
    private int[] output;

    // Start is called before the first frame update
    void Start()
    {
        total = 5;
        count = 1;
        testArray = GetRandomSequence(total, count);
        for (int i = 0; i < count; i++)
        {
            print(testArray[i]);
        }
        print("-----------------------");
        count = 3;
        testArray = GetRandomSequence(total, count);
        for (int i = 0; i < count; i++)
        {
            print(testArray[i]);
        }
        print("-----------------------");
        count = 5;
        testArray = GetRandomSequence(total, count);
        for (int i = 0; i < count; i++)
        {
            print(testArray[i]);
        }
    }

    // Update is called once per frame
    void Update()
    {

    }
    public int[] GetRandomSequence(int total, int count)
    {
        sequence = new int[total];
        output = new int[count];

        for (int i = 0; i < total; i++)
        {
            sequence[i] = i;
        }
        int end = total - 1;
        for (int i = 0; i < count; i++)
        {
            int num = Random.Range(0, end + 1);
            output[i] = sequence[num];
            sequence[num]= sequence[end];
            end--;
        }
        return output;
    }
}

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