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80 lines
1.9 KiB
C++
80 lines
1.9 KiB
C++
#include<iterator>
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#include<iostream>
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#include<vector>
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using namespace std;
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/*****************
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桶排序：将值为i的元素放入i号桶，最后依次把桶里的元素倒出来。
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桶排序序思路：
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1. 设置一个定量的数组当作空桶子。
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2. 寻访序列，并且把项目一个一个放到对应的桶子去。
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3. 对每个不是空的桶子进行排序。
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4. 从不是空的桶子里把项目再放回原来的序列中。
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假设数据分布在[0，100)之间，每个桶内部用链表表示，在数据入桶的同时插入排序，然后把各个桶中的数据合并。
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*****************/
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const int BUCKET_NUM = 10;
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struct ListNode{
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explicit ListNode(int i=0):mData(i),mNext(NULL){}
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ListNode* mNext;
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int mData;
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};
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ListNode* insert(ListNode* head,int val){
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ListNode dummyNode;
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ListNode *newNode = new ListNode(val);
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ListNode *pre,*curr;
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dummyNode.mNext = head;
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pre = &dummyNode;
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curr = head;
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while(NULL!=curr && curr->mData<=val){
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pre = curr;
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curr = curr->mNext;
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}
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newNode->mNext = curr;
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pre->mNext = newNode;
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return dummyNode.mNext;
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}
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ListNode* Merge(ListNode *head1,ListNode *head2){
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ListNode dummyNode;
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ListNode *dummy = &dummyNode;
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while(NULL!=head1 && NULL!=head2){
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if(head1->mData <= head2->mData){
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dummy->mNext = head1;
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head1 = head1->mNext;
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}else{
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dummy->mNext = head2;
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head2 = head2->mNext;
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}
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dummy = dummy->mNext;
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}
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if(NULL!=head1) dummy->mNext = head1;
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if(NULL!=head2) dummy->mNext = head2;
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return dummyNode.mNext;
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}
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void BucketSort(int n,int arr[]){
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vector<ListNode*> buckets(BUCKET_NUM,(ListNode*)(0));
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for(int i=0;i<n;++i){
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int index = arr[i]/BUCKET_NUM;
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ListNode *head = buckets.at(index);
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buckets.at(index) = insert(head,arr[i]);
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}
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ListNode *head = buckets.at(0);
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for(int i=1;i<BUCKET_NUM;++i){
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head = Merge(head,buckets.at(i));
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}
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for(int i=0;i<n;++i){
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arr[i] = head->mData;
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head = head->mNext;
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}
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} |