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This article mainly explains "how to achieve sequence sorting on C++". The content of the explanation in the article is simple and clear, and it is easy to learn and understand. Please follow the editor's train of thought slowly and deeply. Let's study and learn "how C++ can achieve sequence sorting".

Permutation Sequence sequence sorting

The set [1,2,3,...,n] contains a total of n! Unique permutations.

By listing and labeling all of the permutations in order, we get the following sequence for n = 3:

"123"

"132"

"213"

"231"

"312"

"321"

Given n and k, return the kth permutation sequence.

Note:

Given n will be between 1 and 9 inclusive.

Given k will be between 1 and n! Inclusive.

Example 1:

Input: n = 3, k = 3

Output: "213"

Example 2:

Input: n = 4, k = 9

Output: "2314"

The purpose of this problem is to find out the k permutation and combination of n numbers. because of its particularity, we do not have to find all the permutations and combinations, and then return to the k, here we can only find the k permutation and combination. then the difficulty is how to know the order of the numbers. first of all, we should know that when n = 3, there are 3! = 6 kinds of permutations and combinations, when n = 4. There are 4! = 24 permutations and combinations. Here we will analyze them in the case of n = 4 and k = 17. All permutations and combinations are as follows:

1234

1243

1324

1342

1423

1432

2134

2143

2314

2341

2413

2431

3124

3142

3214

3241

3412 = 1;-- I) {int j = k / f [I-1]; k% = f [I-1]; res.push_back (num1); num.erase (j, 1);} return res;}} Thank you for your reading. the above is the content of "how to achieve sequence sorting on C++". After the study of this article, I believe you have a deeper understanding of the problem of how to achieve sequence sorting on C++. The specific use also needs to be verified in practice. Here is, the editor will push for you more related knowledge points of the article, welcome to follow!

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