完成sort

TinySTL/Algorithm.h

@@ -457,8 +457,7 @@ namespace TinySTL{
 				while (n++){
 					--it;
 				}
-			}
-			else{
+			}else{
 				while (n--){
 					++it;
 				}
@@ -478,6 +477,62 @@ namespace TinySTL{
 		typedef iterator_traits<InputIterator>::iterator_category iterator_category;
 		_advance(it, n, iterator_category());
 	}
+	//********** [sort] ******************************
+	//********* [Algorithm Complexity: O(NlogN)] ****************
+	namespace {
+		template<class RandomIterator, class BinaryPredicate>
+		typename iterator_traits<RandomIterator>::value_type
+			mid3(RandomIterator first, RandomIterator last, BinaryPredicate pred){//[first, last]
+			auto mid = first + (last + 1 - first) / 2;
+			if (pred(*mid, *first)){
+				swap(*mid, *first);
+			}
+			if (pred(*last, *mid)){
+				swap(*last, *mid);
+			}
+			if (pred(*last, *first)){
+				swap(*last, *first);
+			}
+			auto ret = *mid;
+			swap(*mid, *(last - 1));//将mid item换位作为哨兵
+			return ret;
+		}
+		template<class RandomIterator, class BinaryPredicate>
+		void bubble_sort(RandomIterator first, RandomIterator last, BinaryPredicate pred){
+			auto len = last - first;
+			for (auto i = len; i != 0; --i){
+				for (auto p = first; p != (first + i - 1); ++p){
+					if (pred(*(p + 1), *p))
+						swap(*(p + 1), *p);
+				}
+			}
+		}
+	}
+	template<class RandomIterator>
+	void sort(RandomIterator first, RandomIterator last){
+		return sort(first, last, less<typename iterator_traits<RandomIterator>::value_type>());
+	}
+	template<class RandomIterator, class BinaryPredicate>
+	void sort(RandomIterator first, RandomIterator last, BinaryPredicate pred){
+		static int n = 1;
+		if (first >= last || first + 1 == last)
+			return;
+		if (last - first <= 20)//区间长度小于等于20的采用冒泡排序更快
+			return bubble_sort(first, last, pred);
+		auto mid = mid3(first, last - 1, pred);
+		auto p1 = first, p2 = last - 2;
+		while (p1 < p2){
+			while (pred(*p1, mid) && p1 < p2) ++p1;
+			while (!pred(*p2, mid) && p1 < p2) --p2;
+			if (p1 < p2){
+				swap(*p1, *p2);
+			}
+		}
+		swap(*p1, *(last - 2));//将作为哨兵的mid item换回原来的位置
+		sort(first, p1);
+		sort(p1 + 1, last);
+	}
+
 }
 
 

TinySTL/Test/AlgorithmTest.cpp

@@ -189,6 +189,29 @@ namespace TinySTL{
 			TinySTL::advance(lit, -5);
 			assert(*vit == 0 && *lit == 0);
 		}
+		void testSort(){
+			int arr1[1] = { 0 };
+			TinySTL::sort(std::begin(arr1), std::end(arr1));
+			assert(std::is_sorted(std::begin(arr1), std::end(arr1)));
+
+			int arr2[2] = { 1, 0 };
+			TinySTL::sort(std::begin(arr2), std::end(arr2));
+			assert(std::is_sorted(std::begin(arr2), std::end(arr2)));
+
+			int arr3[3] = { 2, 1, 3 };
+			TinySTL::sort(std::begin(arr3), std::end(arr3));
+			assert(std::is_sorted(std::begin(arr3), std::end(arr3)));
+
+			int arr4[10000];
+			std::random_device rd;
+			for (auto i = 0; i != 100; ++i){
+				for (auto& n : arr4){
+					n = rd() % 65536;
+				}
+				TinySTL::sort(std::begin(arr4), std::end(arr4));
+				assert(std::is_sorted(std::begin(arr4), std::end(arr4)));
+			}
+		}
 
 
 		void testAllCases(){
@@ -211,6 +234,7 @@ namespace TinySTL{
 			testIsPermutation();
 			testSearch();
 			testAdvance();
+			testSort();
 		}
 	}
 }
\ No newline at end of file

TinySTL/Test/AlgorithmTest.h

@@ -11,6 +11,7 @@
 #include <cstring>
 #include <cassert>
 #include <list>
+#include <random>
 #include <vector>
 
 #include "../BinarySearchTree.h"
@@ -39,6 +40,7 @@ namespace TinySTL{
 		void testIsPermutation();
 		void testSearch();
 		void testAdvance();
+		void testSort();
 
 		void testAllCases();
 	}