- 通过仿函数for_each操作
1 vector myv{ 1,2,3,4,5 };2 listdb{ 1.1,2.2,3.3,4.4,5.5 };3 4 //循环算法,算法的泛型5 print p = for_each(db.begin(), db.end(), print());6 cout << p.count << endl; - find_if查找算法
1 //查找算法2 auto it = find(myv.begin(), myv.end(), 3);3 cout << *it << endl;
- find_if与lambda结合
1 //寻找第一个偶数的位置,返回0就是找到的 2 auto it = find_if(myv.begin(), myv.end(), [](int x)->bool 3 { 4 if (x % 2 == 0) 5 { 6 return 0; 7 } 8 else 9 {10 return 1;11 }12 });13 14 if (it != myv.end())15 {16 cout << *it << " pos=" << it - myv.begin() << endl;17 } - adjacent_find处理相邻的两个数据
1 list mylist{ 3,6,9,11,11,28,20,29 };2 //查找相邻的两个元素相等的位置(adjacent_find处理相邻的两个数据)3 auto it = adjacent_find(mylist.begin(), mylist.end());4 if (it != mylist.end())5 {6 cout << *it << endl;7 it++;8 cout << *it << endl;9 } - adjacent_find与lambda结合
1 //寻找第一个奇偶性不同的 2 auto it = adjacent_find(mylist.begin(), mylist.end(), [](int x,int y)->bool 3 { 4 if ((x - y) % 2 == 0) 5 { 6 return 0; 7 } 8 else 9 {10 return 1;11 }12 });13 if (it != mylist.end())14 {15 cout << *it << endl;16 it++;17 cout << *it << endl;18 } - find_first_of寻找第一个集合在第二个集合中出现的第一个数据
1 char *str1 = "1234567890"; 2 char *str2 = "abcdefg123"; 3 //寻找在string1中第一个出现在string2的字符 4 char *p = find_first_of(str1, str1 + strlen(str1), str2, str2 + strlen(str2)); 5 cout << *p << endl; 6 7 vector myint1{ 1,2,3,4,5 }; 8 vector myint2{ 7,8,9,10,1 }; 9 auto it = find_first_of(myint1.begin(), myint1.end(), myint2.begin(), myint2.end());10 cout << *it << endl; - count与count_if查询数据个数
1 vector myint{ 1,2,3,4,5,6,1,2,3,4 }; 2 int count1 = count(myint.begin(), myint.end(), 3); 3 cout << count1 << endl; 4 5 //查询所有小于4的元素的个数 6 int count2 = count_if(myint.begin(), myint.end(), [](int x) 7 { 8 if (x < 4) 9 {10 return 1;11 }12 else13 {14 return 0;15 }16 });17 cout << count2 << endl; - mismatch判断两个集合是否相等
1 vector myint1{ 1,2,3,4,5,6,1,2,3,4 }; 2 vector myint2{ 1,2,3,4,5,6,1,2,3,4 }; 3 4 auto it = mismatch(myint1.begin(), myint1.end(), myint2.begin()); 5 if (it.first == myint1.end() && it.second == myint2.end()) 6 { 7 cout << "相等" << endl; 8 } 9 else10 {11 //first是第一个容器不匹配的位置(可能为空),second是第二个容器不匹配的位置(可能为空)12 cout << "不相等" << endl;13 cout << *(it.first) <<" " << *(it.second) << endl;14 }1 char *s1[] = { "abc","acv","adf","oop" }; 2 char *s2[] = { "abc","acv","adf","oop","134" }; 3 auto it = mismatch(s1, s1 + 4, s2, [](const char* str1,const char* str2) 4 { 5 if (strcmp(str1, str2) == 0) 6 { 7 return 1; 8 } 9 else10 {11 return 0;12 }13 });14 15 if (it.first == s1 + sizeof(s1)/sizeof(s1[0]) && it.second == s2 + sizeof(s2) / sizeof(s2[0]))16 {17 cout << "相等" << endl;18 }19 else20 {21 //first是第一个容器不匹配的位置(可能为空),second是第二个容器不匹配的位置(可能为空)22 cout << "不相等" << endl;23 //cout << *(it.first) << " " << *(it.second) << endl;24 } - equal判断是否是一样的集合
1 2 3 vector myv1{ 1,2,3,4,5 }; 4 vector myv2{ -1,2,-3,4,-5 }; 5 6 //判断绝对值知否相等 7 if (equal(myv1.begin(), myv1.end(), myv2.begin(), [](int a, int b) ->bool 8 { 9 if (a == abs(b) || b == abs(a))10 {11 return 1;12 }13 else14 {15 return 0;16 }17 }))18 {19 cout << "相等" << endl;20 }21 else22 {23 cout << "不相等" << endl;24 } - search判断有没有连续一样的部分
1 vector myv1{ 1,2 }; 2 vector myv2{ 1,2,3,4,5 }; 3 4 //判断有没有连续相等的子集 5 auto it = search(myv1.begin(), myv1.end(), myv2.begin(), myv2.end()); 6 7 if (it == myv1.end()) 8 { 9 cout << "是子集" << endl;10 }11 else12 {13 cout << "不是子集" << endl;14 } - search_n判断有没有连续一样的数据
1 vector myv1{ 1,2,2,2,3,3,4 }; 2 3 //判断有没有连续相等的数据 4 auto it = search_n(myv1.begin(), myv1.end(),3, 2); 5 6 if (it == myv1.end()) 7 { 8 cout << "有" << endl; 9 }10 else11 {12 cout << "没有" << endl;13 } - 从反向寻找一个集合在另一个集合中出现的位置
1 vector myv2{ 1,2,2,2,3,3,4 };2 vector myv3{ 3,4 };3 //在myv2中从后往前找myv3所在的位置4 auto it = find_end(myv2.begin(), myv2.end(), myv3.begin(), myv3.end());5 6 if(it != myv2.end())7 {8 cout << *it << " " << it - myv2.begin() << endl;9 }