归并排序

#ifndef MERGE_SORT_H
#define MERGE_SORT_H
void mergeArr(int left,int mid,int right,int *arr); 
void mergeSort(int left,int right,int *arr); 
void mergeArr(int left,int mid,int right,int *arr){
	int leftLen=mid-left+1; 
	int rightLen=right-mid; 
	int *leftsubArr=new int[leftLen];
	int *rightsubArr=new int[rightLen]; 
	for(int i=left;i<=mid; i++){
		leftsubArr[i-left]=arr[i]; 
	}
	for(int i=mid+1;i<=right; i++){
		rightsubArr[i-mid-1]=arr[i];
	}
	int i=0; 
	int j=0; 
	while(i<leftLen&&j<rightLen){
		if(leftsubArr[i]<=rightsubArr[j]){
			arr[left+i+j]=leftsubArr[i]; 
			i++; 
		}else{
			arr[left+i+j]=rightsubArr[j]; 
			j++; 
		}
	}
	while(i<leftLen||j<rightLen){
		if(i==leftLen&&j<rightLen){
			arr[left+i+j]=rightsubArr[j]; 
			j++;
		}
		if(j==rightLen&&i<leftLen){
			arr[left+i+j]=leftsubArr[i]; 
			i++; 
		}
	}
}
void mergeSort(int left,int right,int *arr){
	if(left<right){
		int mid=(left+right)/2; 
		mergeSort(left,mid,arr); 
		mergeSort(mid+1,right,arr); 
		mergeArr(left,mid,right,arr); 
	}
}
#endif 

int main(){
	int arr[11]={9,5,10,5,4,12,7,3,2,1,6}; 
	mergeSort(0,10,arr); 
	for(int i=0;i<11; i++){
		std::cout<<arr[i]<<std::endl; 
	}
}