Ch9_StringFind_original.cpp

#include <iostream>
#include <string>
#include <vector>
using namespace std;

int main()
{
	string line1 = "We were her pride of 10 she named us:";
	string line2 = "Benjamin, Phoenix, the Prodigal";
	string line3 = "and perspicacious pacific Suzanne";
	string sentence = line1+' '+line2+' '+line3;
	string separators(" \t:,\v\r\n\f");//用作分隔符的字符
	string word;
	//sentence中最长、最短单词以及下一单词的长度，单词数目
	string::size_type maxLen, minLen, wordLen, count=0;
	//存放最长及最短单词的vector容器
	vector<string> longestWords, shortestWords;
	//单词的起始及结束位置
	string::size_type startPos=0, endPos=0;

	//每次循环处理sentence中的一个单词
	while( (startPos = sentence.find_first_of( separators, endPos ))!= string::npos )
	{   //找到下一个单词的起始位置
		++count;
		//找到下一单词的结束位置
		endPos = sentence.find_first_of(separators,startPos);

		if( endPos == string::npos )//找不到下一个分隔符位置，即该单词是最后一个单词
            wordLen = sentence.size() - startPos;
        else                        //找到下一个出现分隔符的位置
            wordLen = endPos - startPos;

        word.assign( sentence.begin()+startPos,
                    sentence.begin()+startPos+wordLen );//获取单词

        //设置下次查找的起始位置
        startPos = sentence.find_first_not_of( separators, endPos );

        if ( count == 1 ) { //找到的第一个单词
            maxLen = minLen = wordLen;
            longestWords.push_back( word );
            shortestWords.push_back( word );
        }
        else {
            if( wordLen>maxLen ){ //当前单词比目前的最长单词更长
				maxLen = wordLen;
				longestWords.clear(); //清空存放最长单词的容器
				longestWords.push_back( word );
			}
			else if( wordLen == maxLen ) //当前单词与目前的最长单词等长
				longestWords.push_back( word );

			if( wordLen<minLen ){ //当前单词比目前的最长单词更短
				minLen=wordLen;
				shortestWords.clear(); //清空存放最短单词的容器
				shortestWords.push_back( word );
			}
			else if( wordLen == minLen ) //当前单词与目前的最短单词等长
				shortestWords.push_back( word );
        }

	}

	//输出单词数目
	cout << "word amount:" << count << endl;
	vector<string>::iterator iter;

	//输出最长单词
	cout << "longest word(s):" << endl;
	iter = longestWords.begin();
	while( iter != longestWords.end() )
		cout << *iter++ << endl;

	//输出最短单词
	cout << "shortest word(s):" << endl;
	iter = shortestWords.begin();
	while( iter != shortestWords.end() )
		cout << *iter++ << endl;

	return 0;
}