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#include<iostream>
#include<iomanip>
#include<vector>
#include<cstring>
using namespace std;

//快速排序
//unstable
//time: sita(n*lgn) omiga(n*lgn) O(n^2)
//memery O(lgn)
void quicksort(int *a, int *b){ //[a,b)
int *l = a , *r = b-1;
if(l>=r)return;
int *mid = l; //suppose that the little some is in [l,mid-1] and bound is in mid
while(r>mid){
if(*r<*l)swap(*(++mid),*r);
else r--;
}
swap(*l,*mid);
quicksort(a,mid);
quicksort(mid+1,b);
}


//插入排序
//stable
//time: sita(n^2) omiga(n) O(n^2)
//memery: O(1)
void insertionsort(int *a,int *b){
for(int *i = a; i<b; i++){
int *j = i;
while(j>a&&*j<*(j-1)){//可能每次都直接跳出去,结果成了omiga(n)
swap(*j,*(j-1));
j--;
}
}
}


//选择排序
//unstable
//time: sita(n^2) omiga(n^2) O(n^2)
//memery: O(1)
void selectsort(int *a,int *b){
for(int *i=a;i<b;i++){
int*min = i;
for(int *j=i+1;j<b;j++){
if(*min>*j)min=j;
}
swap(*min,*i);
}
}


//基数排序??
//unstable
//time: omige(log(k,maxvalue)*n) O(log(k,maxvalue)*n)
//memery:
void radixsort(int*a,int*b){
const int k =15;
vector<int>bin[2][k+1];// 滚动数组
int t=0;

for(int*i=a;i<b;i++)bin[t][(*i)&k].push_back(*i);
t^=1;

for(int times=1;times<8;times++){
for(int i=0;i<=k;i++)bin[t][i].clear();
for(int i=0;i<=k;i++){
for(int x:bin[t^1][i]){
bin[t][(x>>(4*times))&k].push_back(x);
}
}
t^=1;
}
for(int i=0;i<k;i++){
for(int x:bin[t^1][i]){
*(a++)=x;
}
}
}


//计数排序??
//unstable
//time: sita(maxvalue-minvalue) omiga(maxvalue-minvalue) O(maxvalue-minvalue)
//memery: O(maxvalue-minvalue)
void countingsort(int*a,int*b){
int maxvalue = (1<<31); // 最小的int
int minvalue = -1^(1<<31);// 最大的int
for(int*i=a;i<b;i++){
maxvalue=max(maxvalue,*i);
minvalue=min(minvalue,*i);
}
int*data = new int[maxvalue-minvalue+1];
memset(data,0,sizeof(int)*(maxvalue-minvalue+1));
for(int*i=a;i<b;i++)data[(*i)-minvalue]++;
for(int i=minvalue;i<=maxvalue;i++){
while(data[i-minvalue]--)*(a++)=i;
}
delete[] data;
}


//桶排序??
//time: sita(k*O(sort(n/k)) omiga(k*O(sort(n/k)) O(k*O(sort(n/k))
//memery:
void bucketsort(int*a,int*b){
int maxvalue = (1<<31); // 最小的int
int minvalue = -1^(1<<31);// 最大的int
for(int*i=a;i<b;i++){
maxvalue=max(maxvalue,*i);
minvalue=min(minvalue,*i);
}
if(maxvalue==minvalue)return;
const int k = 10;
vector<int>data[k];
for(int*i=a;i<b;i++){
int belong = ((*i)-minvalue)/((maxvalue-minvalue)/10+1);
data[belong].push_back(*i);
}
for(int i=0;i<k;i++){
sort(data[i].begin(),data[i].end());
for(int x:data[i])*(a++)=x;
}
}


//冒泡排序
//stable
//time: sita(n^2) omiga(n) O(n^2)
//memery: O(1)
void bubblesort(int*a,int *b){
for(int i=0;i<b-a;i++){
bool noswap = true;
for(int*j=a+1;j<b-i;j++){
if(*(j-1)>*j){
swap(*(j-1),*j);
noswap = false;
}
}
if(noswap)break;
}
}


//归并排序
//stable
//time: sita(n*lgn) omiga(n*lgn) O(n*lgn)
//memery: O(n)
void mergesort(int*a,int*b){
int*mid = a+ (b-a)/2; // =(a+b)/2
if(a>=b-1)return;

mergesort(a,mid);
mergesort(mid,b);

int*c=new int[b-a];
int*pa=a,*pm=mid,*pc=c;
while(pa<mid&&pm<b){
*(pc++)=*pa<=*pm?*(pa++):*(pm++);
}
while(pa<mid)*(pc++)=*(pa++);
while( pm<b )*(pc++)=*(pm++);
memcpy(a,c,sizeof(int)*(b-a));
}


//希尔排序
//unstable
//time: sita(n^1.3) omiga(??) O(n^2)
//memery: O(1)
void shellsort(int*a,int*b){
for(int gap=(b-a)>>1;gap;gap>>=1){//枚举gap
for(int*i=a+gap;i<b;i++){
int x=*i,*j=i;
while(j-gap>=a&&x<*(j-gap)){
*j=*(j-gap);
j-=gap;
}
*j=x;
}
}
}


//堆排序
//unstable
//time: sita(n*lgn) omiga(n*lgn) O(n*lgn)
//memery: O(1)
void heapsort(int*a,int*b){
const int n=b-a;
a--;

//up
for(int i=1;i<=n;i++){//建立大根堆
int j=i;
while(j!=1&&a[j]>a[j>>1]){//不是根且比父亲大
swap(a[j],a[j>>1]);
j>>=1;
}
}

//down
for(int i=n;i>=1;i--){
swap(a[1],a[i]);
int cur = 1;
while((cur<<1)<i){//左儿子存在
int son = (cur<<1|1)<i && a[cur<<1|1]>a[cur<<1];//若满足此条件则son为1,代表着右儿子优先
if(a[cur]<a[cur<<1|son])swap(a[cur],a[cur<<1|son]);
else break;//若优先的儿子都不能换
cur = cur<<1|son;
}
}
}


const int n = 1e4;
int ans[n];

inline void compare(int *a,int *b,void sort(int*,int*),string name){
int data[n];
memcpy(data,a,sizeof(int)*(b-a));
time_t begin = clock();
sort(data, data+n);
time_t spend = clock()-begin;
cout<<setw(16)<<std::left<<name<<" time:"<<setw(13)<<spend;
//check it
for(int i=0;i<n;i++){
if(ans[i]==data[i]&&i==n-1)cout<<"everything is right"<<endl;
else if(ans[i]!=data[i]){
cout<<"error"<<endl;
break;
}
}
}

int main(){
srand(int(time(NULL)));

int a[n];
for(int i=0;i<n;i++)a[i]=rand()%9000000+1000000;
memcpy(ans,a,sizeof(a));
sort(ans,ans+n);

compare(a,a+n,sort,"* STL(fastest)");
compare(a,a+n,quicksort,"quicksort");
compare(a,a+n,insertionsort,"insertionsort");
compare(a,a+n,selectsort,"selectsort");
compare(a,a+n,radixsort,"radixsort");
compare(a,a+n,countingsort,"countingsort");
compare(a,a+n,bucketsort,"bucketsort");
compare(a,a+n,bubblesort,"bubblesort");
compare(a,a+n,mergesort,"mergesort");
compare(a,a+n,shellsort,"shellsort");
compare(a,a+n,heapsort,"heapsort");

puts("ok");
}



/*

输出:

* STL(fastest) time:468 everything is right
quicksort time:1265 everything is right
insertionsort time:178130 everything is right
selectsort time:126705 everything is right
radixsort time:3128 everything is right
countingsort time:50445 everything is right
bucketsort time:1002 everything is right
bubblesort time:355497 everything is right
mergesort time:3295 everything is right
shellsort time:3960 everything is right
heapsort time:2347 everything is right
ok


*/

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