- 如果容器中是类,如果要调用sort则需要重载操作符 "<"
- 包含头文件
1 #define _CRT_SECURE_NO_WARNINGS 2 #include <vector> 3 #include <list> 4 #include <algorithm> 5 #include <iostream> 6 #include <algorithm> 7 #include <string> 8 #include <iterator> 9 using namespace std;
- 通过结构体vector对象数组与仿函数对对象进行排序
1 //vector结构体排序 2 struct student 3 { 4 int score; 5 char name[20]; 6 student(int s, char *n) 7 { 8 score = s; 9 strcpy(name, n); 10 } 11 //需要重载小于运算符来对vector数组进行排序 12 bool operator <(const student &s2) 13 { 14 if (this->score > s2.score) 15 { 16 return 1; 17 } 18 else 19 { 20 return 0; 21 } 22 } 23 }; 24 25 void main1() 26 { 27 vector<student> mylist{ {100,"1"},{99,"2"},{88,"3"},{ 77,"4" } }; 28 //取前两名 29 partial_sort(mylist.begin(), mylist.begin() + 2, mylist.end()); 30 31 for (auto i : mylist) 32 { 33 cout << i.name <<" " << i.score << endl; 34 } 35 36 cin.get(); 37 }
- sort()对数组进行排序,以及取出前三名
1 //数组的sort 2 { 3 vector<int> mylist{ 1,9,2,8,3,7 }; 4 sort(mylist.begin(), mylist.end()); 5 for (auto i : mylist) 6 { 7 cout << i << endl; 8 } 9 } 10 cout << endl; 11 12 //只取一部分(比如对一串数据只取前三名) 13 { 14 vector<int> mylist{ 1,9,2,8,3,7 }; 15 partial_sort(mylist.begin(), mylist.begin() + 4, mylist.end()); 16 for (auto i : mylist) 17 { 18 cout << i << endl; 19 } 20 }
- 全排列,一直对调,随机打乱,一直到升序的时候不能再打乱
1 //全排列 2 //一直对调,随机打乱,一直到升序的时候不能再打乱 3 { 4 int a[5] = { 9,5,3,4,5 }; 5 int count = 0; 6 do 7 { 8 for (auto i : a) 9 { 10 cout << i; 11 } 12 cout << endl; 13 count++; 14 } while (prev_permutation(a, a + 5)); 15 cout << count << endl; 16 }
- 全排列随机对调,直到降序不能再打乱
1 int a[5] = { 9,5,3,4,5 }; 2 int count = 0; 3 do 4 { 5 for (auto i : a) 6 { 7 cout << i; 8 } 9 cout << endl; 10 count++; 11 //如果有序,则返回值是零 12 } while (next_permutation(a, a + 5)); 13 cout << count << endl;
- 自动对字符串进行排序
1 char *s1 = "book"; 2 char *s2 = "hello"; 3 bool res = lexicographical_compare(s1, s1 + strlen(s1), s2, s2 + strlen(s2)); 4 if (res) 5 { 6 cout << "s1在s2前面" << endl; 7 } 8 else 9 { 10 cout << "s1在s2后面" << endl; 11 }
- 分块排序,小的向左,大 的向右
1 //分块排序 2 { 3 int a[15] = { 3,4,5,6,7,8,32,23,4325,65,56,5,34,43,3 }; 4 //以a+8为中心,小于向左,大于向右 5 nth_element(a, a + 8, a + 14); 6 for_each(a, a + 14, [](int x) {cout << x << endl; }); 7 }
- 求最大最小
1 { 2 //求最大值最小值 3 int a = max({ 1,2,3,4,5 }); 4 int b = min({ 1,2,3,4,5 }); 5 auto it = minmax({ 1,2,3,4,5 }); 6 cout << a << endl; 7 cout << it.first << endl; 8 cout << it.second << endl; 9 }
- 判断是全满足还是部分满足还是都不满足
1 //all_of 全部满足 2 //any_of 至少有一个满足 3 //none_of 都不满足 4 { 5 vector<int> myint{ 1,2,3,4,5 }; 6 bool isit = all_of(myint.begin(), myint.end(), [](int i)->bool {return i % 2 != 0; }); 7 //类似还有 any_of none_of 8 if (isit) 9 { 10 cout << "OK" << endl; 11 } 12 else 13 { 14 cout << "NOT OK" << endl; 15 } 16 }
- 条件拷贝
1 //copy_if 条件拷贝 2 { 3 vector<int> v1{ 1,2,3,4,5 }; 4 vector<int> v2(v1.size()); 5 auto it = copy_if(v1.begin(), v1.end(), v2.begin(),[](int i) {return i % 2; }); 6 //压缩容器 7 v1.resize(distance(v2.begin(), it)); 8 }
- 部分排序以后复制到另外一个容器对副本进行操作(局部排序)
1 void main22() 2 { 3 //数组的sort 4 { 5 vector<int> mylist{ 1,9,2,8,3,7 }; 6 int a[6]{ 0 }; 7 partial_sort_copy(mylist.begin(), mylist.end(), a, a + 6); 8 } 9 cin.get(); 10 }
- 容器二分查找
1 void main3() 2 { 3 int a[10] = { 1,9,2,8,3,7,4,6,5,0 }; 4 //默认从小到大 5 sort(a, a + 10, [](int a, int b) {return a < b; }); 6 for (auto i : a) 7 { 8 cout << i << endl; 9 } 10 11 //取数组中的最小值 12 cout << *min_element(a, a + 10) << endl; 13 //取数组中的最大值 14 cout << *max_element(a, a + 10) << endl; 15 16 //二分查找(必须从小到大) 17 auto it = binary_search(a, a + 10, 4); 18 if (it) 19 { 20 cout << "find" << endl; 21 } 22 else 23 { 24 cout << "not find" << endl; 25 } 26 cin.get(); 27 }
- max min操作
1 //取max 2 void main4() 3 { 4 int num1 = max(100, 90); 5 int num2 = min(100, 90); 6 cout << max((char *)"123", (char *)"234", [](const char *str1, const char *str2)->bool {return strcmp(str1, str2) < 0; }); 7 8 cin.get(); 9 }
- 两个容器归并排序
1 //用于归并的字符串模板 2 //template<class T> 3 //bool greater(T t1, T t2) 4 //{ 5 // return t1 < t2; 6 //} 7 8 //也可以用仿函数 9 template<class T> 10 class greater 11 { 12 public: 13 bool operator ()(T t1, T t2) 14 { 15 return t1 < t2; 16 } 17 }; 18 //两个数组归并排序 19 void main5() 20 { 21 int a[10] = { 1,9,2,8,3,7,4,6,5,0 }; 22 int b[5]{ 1, 9, 2, 8, 3 }; 23 int c[15]{ 0 }; 24 //从大到小排序 25 sort(a, a + 10, [](int a, int b) {return a > b; }); 26 sort(b, b + 5, [](int a, int b) {return a > b; }); 27 //通过lambda 28 //merge(a, a + 10, b, b + 5, c, [](int a, int b) {return a > b; }); 29 30 //通过仿函数 31 merge(a, a + 10, b, b + 5, c, greater<int>()); 32 for (auto i : c) 33 { 34 cout << i << endl; 35 } 36 cin.get(); 37 }
- 判断是否有连续相等区间
1 //判断是否是包含关系(要在realease下执行) 必须要连续相等 2 void main6() 3 { 4 int a[10] = { 1,9,2,8,3,7,4,6,5,0 }; 5 int b[5] = { 1,9,5,8,7 }; 6 bool check = includes(a, a + 10, b, b + 4); 7 if (check) 8 { 9 cout << "包含" << endl; 10 } 11 else 12 { 13 cout << "不包含" << endl; 14 } 15 16 cin.get(); 17 }
- 求两个容器交并集
1 //求并集 2 void main7() 3 { 4 int a[10] = { 1,9,2,8,3,7,4,6,5,0 }; 5 int b[5] = { 1,99,5,8,7 }; 6 //这种操作重复数据会被省略(第一个不重复的后面会被保留) 7 /*set_union(a, a + 10, b, b + 5, ostream_iterator<int>(cout, " "));*/ 8 //这种操作会都保留 9 int c[15]{ 0 }; 10 set_union(a, a + 10, b, b + 5, c); 11 for (auto i : c) 12 { 13 cout << i << endl; 14 } 15 cin.get(); 16 }
- 把一个数组转化成一个堆
1 //把一个数组转成一个堆 2 void main8() 3 { 4 int a[10]{ 4,5,6,7,8,10,1,9,2,0 }; 5 6 //创建一个堆(创建一个最小堆:顶部值最小) 7 make_heap(a, a + 10, [](int a, int b)->bool {return a > b; }); 8 for (auto i : a) 9 { 10 cout << i << endl; 11 } 12 cout << endl << endl; 13 14 //将第一个最大元素移动到最后，同时将剩下的元素重新构造成一个新的heap。 15 /*pop_heap(a, a + 10); 16 for (auto i : a) 17 { 18 cout << i << endl; 19 } 20 cout << endl << endl;*/ 21 22 //堆排序(最小堆sort_heap是从大到小排序,最大堆sort_heap是从小到大排序) 23 sort_heap(a, a + 10,[](int a, int b)->bool {return a > b; }); 24 for (auto i : a) 25 { 26 cout << i << endl; 27 } 28 cout << endl << endl; 29 cin.get(); 30 }
- 内部区间归并排序(需要有两个个排序好子列)
1 //内部区间归并排序(需要有两个个排序好子列) 2 void main9() 3 { 4 int a[10] = { 2,4,6,8,10,1,3,5,7,9 }; 5 //inplace_merge(a, a + 5, a + 10); 6 int b[10] = { 10,8,6,4,2,9,7,5,3,1 }; 7 inplace_merge(b, b + 5, b + 10, [](int a, int b)->bool {return a > b; }); 8 for (auto i : b) 9 { 10 cout << i << endl; 11 } 12 cin.get(); 13 }
- 判断容器是否有序
1 //判断是否有序 2 void main10() 3 { 4 int a[10] = { 1,2,3,4,5,6,7,8,9 }; 5 if (is_sorted(a, a + 10)) 6 { 7 cout << "有序" << endl; 8 } 9 cin.get(); 10 }
- 取出第n大的数据并排好序
1 //取出第n大数据并排好序 2 void main11() 3 { 4 int a[10] = { 99,2,3,4,5,6,7,8,9 }; 5 nth_element(a, a + 3, a + 10); 6 for (auto i : a) 7 { 8 cout << i << endl; 9 } 10 cin.get(); 11 }
- 求出数组中第一个大于(大于等于)某个数的数据
1 //求出数组中第一个大于(大于等于)某个数的数据 2 void main12() 3 { 4 //需要有序 5 int a[10] = { 1,2,3,4,5,6,7,9,20}; 6 //寻找数组中第一个大于等于的数据 7 int *p = lower_bound(a, a + 10, 8); 8 cout << "last:" << *p << endl; 9 10 //寻找第一个大于的数据 11 int *p2 = upper_bound(a, a + 10, 5); 12 cout << "last:" << *p2 << endl; 13 14 for (auto i : a) 15 { 16 cout << i << endl; 17 } 18 cin.get(); 19 }
- 处理有序数组中的重复序列,红黑树的每一个结点是一个链表
1 //处理有序数组中的重复序列,红黑树的每一个结点是一个链表 2 void main13() 3 { 4 int a[10] = { 1,2,3,4,5,27,27,35,39,50 }; 5 pair<int *, int *> range = equal_range(a, a + 10, 27); 6 cout << *range.first << endl; 7 cout << *range.second << endl; 8 for_each(range.first, range.second, [](int x) {cout << x << endl; }); 9 cin.get(); 10 }
- 求两个容器交集差集,以及各自独有的汇总到一起
1 //求两个容器交集差集,以及各自独有的汇总到一起 2 void main() 3 { 4 int a[5] = { 1,2,3,4,5 }; 5 int b[5] = { 1,2,6,7,8 }; 6 int c[2] = { 0 }; 7 //求交集 8 set_intersection(a, a + 5, b, b + 5, c); 9 //求差集(a中有b中没有的数据存到d里面) 10 int d[6]{ 0 }; 11 set_difference(a, a + 5, b, b + 5, d); 12 int e[6]{ 0 }; 13 //将a,b各自独有的汇总到一起 14 set_symmetric_difference(a, a + 5, b, b + 5, e); 15 for (auto i : c) 16 { 17 cout << i << endl; 18 } 19 cin.get(); 20 }