泛型算法系列18:remove()&&remove_copy()

最新推荐文章于 2024-06-26 10:00:00 发布

原创最新推荐文章于 2024-06-26 10:00:00 发布 · 1k 阅读

0 ·

CC 4.0 BY-SA版权

文章标签：

#算法 #vector #class #each #iterator

C++ STL 专栏收录该内容

36 篇文章

订阅专栏

本文通过一个C++程序示例展示了如何从标准模板库(STL)的向量中移除特定值，包括使用remove和erase方法的步骤，并介绍了自定义函数实现remove_copy功能。

// remove.cpp : Defines the entry point for the console application. // #include "stdafx.h" #include <algorithm> #include <vector> #include <iostream> /* ﾊ莎・ original vector sequence: 0 1 0 2 0 3 0 4 0 5 vector after remove, without applying erase(): 1 2 3 4 5 3 0 4 0 5 vector after erase(): 1 2 3 4 5 array after remove_copy(): 1 2 3 4 5 */ template<class _II, class _Ty> inline _II my_find(_II _F, _II _L, const _Ty& _V) { for (; _F != _L; ++_F) if (*_F == _V) break; return (_F); } template<class _II, class _OI, class _Ty> inline _OI my_remove_copy(_II _F, _II _L, _OI _X, const _Ty& _V) { for (; _F != _L; ++_F) if (!(*_F == _V)) *_X++ = *_F; return (_X); } template<class _FI, class _Ty> inline _FI my_remove(_FI _F, _FI _L, const _Ty& _V) { _F = find(_F, _L, _V); if (_F == _L) return (_F); else { _FI _Fb = _F; return (my_remove_copy(++_F, _L, _Fb, _V)); } } using namespace std; void element_print(int val) { cout << val << " "; } int main(int argc, char* argv[]) { int value = 0; int ia[] = { 0, 1, 0, 2, 0, 3, 0, 4, 0, 5 }; vector< int > vec( ia, ia + 10 ); vector< int >::iterator vec_iter; cout << "original vector sequence:/n"; for_each(vec.begin(), vec.end(), element_print); cout << '/n'; vec_iter = my_remove( vec.begin(), vec.end(), value ); cout << "vector after remove, without applying erase():/n"; for_each(vec.begin(), vec.end(), element_print); cout << '/n'; // erase the invalid elements from container vec.erase( vec_iter, vec.end() ); cout << "vector after erase():/n"; for_each(vec.begin(), vec.end(), element_print); cout << '/n'; int ia2[5]; vector< int > vec2( ia, ia+10 ); my_remove_copy( vec2.begin(), vec2.end(), ia2, value ); cout << "array after remove_copy():/n"; for_each(vec.begin(), vec.end(), element_print); cout << '/n'; return 0; }