C++折半插入排序 C++实现折半插入排序（BinaryInsertSort）

// 二分插入：较插入排序，减少了比较的次数，但是插入时间还是一样
// 时间复杂度还是:O(n*n)
#include <iostream>
using namespace std;
 
const int maxSize = 20;
 
template <class T>
void BinInsertSort(T arr[], const int left, const int right) {
 int i, j, low, high, mid;
 T temp;
 
 for(i = left+1; i <= right; i++) {
  temp = arr[i]; // 暂存arr[i]
  low = left;
  high = i-1; // low、high作为折半查找的上、下界
  while(low <= high) { // 用折半查找的方法，查找arr[i]的插入位置
   mid = (low + high) / 2;
   if(temp < arr[mid])
    high = mid - 1;
   else
    low = mid + 1;
  } // while
  for(j = i-1; j >= low; j--)
   arr[j+1] = arr[j]; // 顺序后移
  arr[low] = temp; // 回填
 } // for
} // BinInsertSort
 
int main(int argc, const char * argv[]) {
 int i, n, arr[maxSize];
 
 cout << "请输入要排序的数的个数：";
 cin >> n;
 cout << "请输入要排序的数：";
 for(i = 0; i < n; i++)
  cin >> arr[i];
 cout << "排序前：" << endl;
 for(i = 0; i < n; i++)
  cout << arr[i] << " ";
 cout << endl;
 BinInsertSort(arr, 0, n-1);
 cout << "排序后：" << endl;
 for(i = 0; i < n; i++)
  cout << arr[i] << " ";
 cout << endl;
 return 0;
}