How Can Recursive Functions Be Used to Generate All Permutations of a String or Integer?

Generate string and integer arrangement

A common programming challenge is to list all the possible arranges of the given string or integer. This problem needs to be solved.

Arrangement logic

The logic core behind the arrangement is very simple:

The arrangement of the unit element is the element itself.

For a set of elements, each arrangement is the series of every arrangement of any element and the other elements.
2. Recursive solution

The following recursion function generates arranged: (Here we should insert the same code block as the original text, but describe it in a more natural language)

The recursive function generates all possible arrangements by iterating the arrangement of each element and the remaining elements. When there is only one element, the recursion ends, and the element itself is arranged.

C# implementation

The following C#function is efficiently generated to generate all the arrangement of the given string efficiently, and builds each arrangement from a smaller arrangement by recursively:

This function generates all arrangements by recursively calling itself, and uses

function exchange characters to generate different arrangement combinations.

provides a clearer output result.

<code class="language-csharp">class Program
{
    public static void GetPer(char[] list)
    {
        int x = list.Length - 1;
        GetPer(list, 0, x);
    }

    private static void GetPer(char[] list, int k, int m)
    {
        if (k == m)
        {
            Console.WriteLine(new string(list)); // 使用更清晰的输出方式
        }
        else
            for (int i = k; i <= m; i++)
            {
                   Swap(ref list[k], ref list[i]);
                   GetPer(list, k + 1, m);
                   Swap(ref list[k], ref list[i]);
            }
    }

    static void Swap(ref char a, ref char b)
    {
        char temp = a;
        a = b;
        b = temp;
    }

    static void Main()
    {
        string str = "sagiv";
        char[] arr = str.ToCharArray();
        GetPer(arr);
    }
}</code>

This function effectively generates all possible arrangements of the given string, and builds each arrangement by recursively from smaller arrangement.

The above is the detailed content of How Can Recursive Functions Be Used to Generate All Permutations of a String or Integer?. For more information, please follow other related articles on the PHP Chinese website!