class Sort{
public:
	void MaoPao_Sort(vector<int> &arr){
		//1.判斷溢出條件
		if(arr.size() <2) return;
		int length =arr.size(); 
		for(int i =0;i < length;i++){
			for(int j=0; j < length -i -1 ;j++){
				if(arr[j] >arr[j+1]){
					int temp = arr[j];
					arr[j]= arr[j+1];
					arr[j+1]=temp;
				}
			}
		}
	}		
};

class Sort{
public:
	void Insert_Sort(vector<int> &arr){
		//1.判斷溢出條件
		if(arr.size() < 2) return;
		int length =arr.size();
		int j =0;//初始的已排序區(qū)間的下標 
		for(int i =1;i < length ;i++){ //從未排序的區(qū)間里面取元素
			int temp =arr[i];
			j =i-1;    //不斷更新已排序區(qū)間
			while(j >= 0 && temp <a[j]){
				//如果小的話就往后移動，找到合適的插入位置 
				arr[j+1]=arr[j];
				j--; 
			} 
			arr[j+1]=temp;  //插入元素 
		} 
	}
};

class Sort{
public:
	void Select_Sort(vector<int> &arr ,int length){
		for(int i =0;i < length -1;i++){
			int min_number =arr[i];
			int flag = i;
			for(int j =i;j <length ;j++){
				if(min_number > arr[j]){
					min_number = arr[j];
					flag =j;
				}
			}
			//交換數(shù)字
			arr[flag] =arr[i];
			arr[i]=min_number; 
		}
	}
}; 

class Sort{
public:
	//歸并排序 
	void MergeSort(vector<int> & arr){
		if(arr.size() < 2){
			return ;
		} 
		//拆分函數(shù) 
		Merge_Process(arr,0,arr.size())-1);
	}
	//先拆分，這是拆分函數(shù) 
	void Merge_Process(vector<int> &arr,int start,int end){
		//遞歸拆分，首先需要遞歸的終止條件
		if(end -start == 0) return;
		int mid =((end -start)/2) +start;
		Merge_Process(arr,start,mid);
		Merge_Process(arr,mid+1,end);
		//在合并
		Merge(arr,start,mid,end); 
	} 
	//合并函數(shù)
	void Merge(vector<int> &arr,int start,int mid, int end){
		vector<int> temp(end-start+1,0);//初始化一個臨時數(shù)組
		int tempIndex =0; //輔助空間索引
		int leftIndex =start;
		int rightIndex =mid+1;
		while(leftIndex <= mid && rightIndex <= end){
			if(leftIndex <rightIndex){
				temp[tempIndex++] =arr[leftIndex++]; 
			}else{
				temp[tempIndex++] =arr[rightIndex++];
			}	 
		}
		while(leftIndex <= mid){
			temp[tempIndex++]=arr[leftIndex++];
		} 
		while(rightIndex <= end){
			temp[tempIndex++]=arr[rightIndex++];
		}
		for(int i =0;i< temp.size();i++){
			arr[start+i]=temp[i];
		}
	}
}; 

class Sort{
public:
	void quickSort(vector<int> &arr,int begin, int low){
		if(begin <end){
			//產(chǎn)生一個隨機值 
			int index =rand()%(end-begin+1)+begin;
			//然后把產(chǎn)生的這個隨機值，替換到數(shù)組的首位 
			swap(arr[begin],arr[index]); 
			int i =begin;
			int j =end;
			int base =arr[i];//基準位
			while(i <j){
				while(i<j&& arr[j] >= base){
					j--;
				}
				num[i]=num[j];
				while(i<j && arr[i] < base){
					i++;
				}
				num[j]=num[i];
			}
			//回歸基準位 
			num[i]=base;
			//遞歸開始處理子問題 
			quickSort(arr,begin,i-1);
			quickSort(arr,i+1,end); 
			 
		}
	}
};