所有 N 的 k 组合数

Question

我正在尝试编写一个算法，该算法返回一个数组，该数组包含长度为 n 的值 0、1 和 2 的所有可能组合。

例如，当 n = 2 时：

00

01

02

10

11

12

20

21

22

我已经开始但远未正确或完成的代码：

func main() {

    var results []string

    matches := rangeSlice(2)

    for a := 0; a < len(matches); a++ {

        for b := 0; b < 3; b++ {

            matches[(len(matches) - a) - 1] = b

            results = append(results, strings.Join(convertValuesToString(matches), ""))

        } 

    }

    printResults(results)

}

非常感谢您的帮助！

Answer 1

这只是计数（以k为基数）。您可以这样做——将连续的整数转换为以k为底的整数——但这是很多除法和余数，因此您不妨使用更简单的方法。从n 个0开始，然后尽可能多地重复：将所有尾随的k&nbsp;-1 变为0，然后将前一个元素加1。如果没有前面的元素，你就完成了。如果有助于理解，你可以试试k&nbsp;=10，这是普通的十进制计数。例如：3919 → 将尾随 9 改成 0，1 加 1，结果 39203920 → 末尾没有 9，0 加一，结果 3921...3999 → 将三个尾随的 9 变为 0，将 1 加到 3，结果 4000

Answer 2

试试这个代码！代码 ：n = int(input("Enter value of n :"))result=[]for num1 in range(0,n+1):&nbsp; &nbsp; for num2 in range(0,n+1):&nbsp; &nbsp; &nbsp; &nbsp; result.append(str(num1)+str(num2))print(result)输出 ：Enter value of n :3&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&nbsp;['00', '01', '02', '03', '10', '11', '12', '13', '20', '21', '22', '23', '30', '31', '32', '33']

Answer 3

这是 rici 解决方案（计数）的实现。（输出是二维切片的形式，每个切片都是一个组合。）要生成您的示例输出，getCombinations(3, 2).func getCombinations(base, length int) [][]int {&nbsp; &nbsp; // list of combinations always includes the zero slice&nbsp; &nbsp; combinations := [][]int{make([]int, length)}&nbsp; &nbsp; current := make([]int, length)&nbsp; &nbsp; for {&nbsp; &nbsp; &nbsp; &nbsp; incrementIndex := length - 1&nbsp; &nbsp; &nbsp; &nbsp; // zero trailing <base - 1>'s&nbsp; &nbsp; &nbsp; &nbsp; for current[incrementIndex] == base-1 {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; current[incrementIndex] = 0&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; incrementIndex--&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; // stop when the next digit to be incremented is "larger"&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; // than the specified (slice) length&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; if incrementIndex < 0 {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; return combinations&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; // increment the least significant non-<base - 1> digit&nbsp; &nbsp; &nbsp; &nbsp; current[incrementIndex]++&nbsp; &nbsp; &nbsp; &nbsp; // copy current into list of all combinations&nbsp; &nbsp; &nbsp; &nbsp; combinations = append(combinations, append([]int{}, current...))&nbsp; &nbsp; }}