定制操作->lambda表达式

C++容器单词筛选

最新推荐文章于 2024-09-28 00:47:00 发布

翻译最新推荐文章于 2024-09-28 00:47:00 发布 · 121 阅读

本文介绍了一个使用C++实现的程序，该程序能够从输入的字符串容器中筛选出字符数大于等于指定长度的所有单词，并统计并输出这些单词的数量。通过使用标准库中的vector、sort、unique、find_if和for_each等函数，程序首先对单词进行去重和排序，然后找出满足条件的单词并打印。

//求容器中单词字符数大于等于sz的个数及输出这些单词
#include<iostream>
#include<vector>
#include<string>
#include<algorithm>
using namespace std;
//words or word
string make_plural(size_t ctr, const string &word, const string &ending)
{
	return (ctr > 1) ? word + ending : word;
}
//重排
void elimDups(vector<string> &words)
{
	sort(words.begin(), words.end());
	auto end_unique = unique(words.begin(), words.end());
	words.erase(end_unique, words.end());
}

void biggies(vector<string> &words, vector<string>::size_type sz)
{
	elimDups(words);//对words进行重排
	stable_sort(words.begin(), words.end(), [](const string &s1, const string &s2) {return s1.size() < s2.size(); });//	相当于stable_sort(words.bengin(),words.end(),isShorter);
	auto wc = find_if(words.begin(), words.end(), [sz](const string &a) {return a.size() >= sz; });//返回的是首个满足lambda表达式的迭代器
	auto count = words.end() - wc;//iter1-iter2表示两迭代器之间的距离
	cout << count << " " << make_plural(count, "word", "s") << " of length " << sz << " or longer " << endl;
	for_each(wc, words.end(), [](const string &s) { cout << s << endl; });
	cout << endl;
}

int main()
{
	vector<string> vec;
	string s;
	while (cin >> s)
	{
		vec.push_back(s);
	}
	biggies(vec, 5);
	return 0;
}