提取字符串，并对字符串按字典序排序

    从标准输入读取任意多个字符串，字符串用#分割。最后输入一个固定的标识输入结束的字符串，如“;\*.”，对输入的所有字符串按字典序排，并输出到一个文件中。同时统计字符串的个数、最长字符串和最短字符串。

使用strtok提取字符串

////  main.cpp//  str////  Created by Bryan on 14-6-28.//  Copyright (c) 2014年 Bryan. All rights reserved.//#include <iostream>#include <string>#include <vector>#include <algorithm>using namespace std;struct myStr{    string s;    int len;};bool SortByAlpha(myStr &a, myStr &b){    return a.s<b.s;}bool SortByStrLen(myStr &a, myStr &b){    return a.len<b.len;}vector<myStr> ExtractString(const string &str){    vector<myStr> ret;         char * cstr = new char[str.length() + 1];    strcpy(cstr,str.c_str());    char * p = strtok(cstr, "#;\\*.");    while(p)    {        string tmpS(p);        int len = tmpS.length();        myStr tmp;        tmp.s = tmpS;        tmp.len = len;        ret.push_back(tmp);        p = strtok(NULL, "#;\\*.");    }        return ret;    }int main(int argc, const char * argv[]){    string str;    cout<<"Please enter a string:";    cin>>str;        vector<myStr> ret = ExtractString(str);    cout<<"Before Sort:"<<endl;    for(vector<myStr>::iterator it = ret.begin(); it != ret.end();it++)    {        cout<<it->s<<endl;    }    cout<<endl;    cout<<"After Sort By alphabet:"<<endl;        sort(ret.begin(),ret.end(),SortByAlpha);    for(vector<myStr>::iterator it = ret.begin(); it != ret.end();it++)    {        cout<<it->s<<endl;    }    cout<<endl;    cout<<"After Sort By strLength:"<<endl;    sort(ret.begin(),ret.end(),SortByStrLen);    for(vector<myStr>::iterator it = ret.begin(); it != ret.end();it++)    {        cout<<it->s<<"  length:  "<<it->len<<endl;    }        return 0;}

之前自己写的方法，跟库函数相比麻烦太多

#include <iostream>#include <fstream>#include <vector>const int N = 1000;using namespace std;struct struct_str{char* ch;int length;};int StrDeal(char* str,std::vector<struct_str>& strvector){int strEnd = 0;int i = 0;while(str[i] != '\0'){if(str[i] == ';' && str[i+1] == '\\' && str[i+2] == '*' && str[i+3] == '.')break;i++;}strEnd = i-1;int localStrStart = 0;int localStrEnd = 0;while(str[localStrStart] == '#' && localStrStart<= strEnd)localStrStart++;localStrEnd = localStrStart;while(localStrEnd <= strEnd){while(str[localStrEnd] != '#' && localStrEnd <= strEnd)localStrEnd++;struct_str tmpStrStruc;tmpStrStruc.ch = new char[N];int tmpStrLen = localStrEnd - localStrStart;for(int i = 0;i < tmpStrLen;i++)tmpStrStruc.ch[i] = str[localStrStart + i];tmpStrStruc.ch[tmpStrLen] = '\0';tmpStrStruc.length = tmpStrLen;strvector.push_back(tmpStrStruc);localStrStart = localStrEnd + 1;localStrEnd = localStrStart;while(str[localStrStart] == '#' && localStrStart<= strEnd)localStrStart++;localStrEnd = localStrStart;}return strvector.size();}void StrCmp(std::vector<struct_str>& strvector){int countN = strvector.size();int *a = new int[countN];for(int i = 0;i<countN;i++)a[i] = i;/*for(int j = 1;j < countN;j++){int k = j - 1;int tmp = a[j];while(k >= 0 && strcmp(strvector[a[k]].ch,strvector[a[j]].ch) > 0){a[k+1] = a[k];k = k-1;}a[k+1] = tmp;}*/char myStr[N];int tmp;for(int i = 0;i<countN;i++)for(int j = i;j<countN;j++){if(strcmp(strvector[i].ch,strvector[j].ch)>0){strcpy(myStr,strvector[i].ch);strcpy(strvector[i].ch,strvector[j].ch);strcpy(strvector[j].ch,myStr);tmp = strvector[i].length;strvector[i].length = strvector[j].length;strvector[j].length = tmp;}}for (int i = 0;i<countN;i++){cout<<strvector[i].ch<<endl;}int maxLen = strvector[0].length;int minLen = strvector[0].length;int maxIndex = 0;int minIndex = 0;for(int i = 0;i< countN;i++){if(strvector[i].length > maxLen){maxIndex = i;maxLen = strvector[i].length;}if(strvector[i].length < minLen){minIndex = i;minLen = strvector[i].length;}}ofstream out("result.txt",ios::out);if(!out){cerr<<"Open file error!";exit(1);}for(int i=0;i<countN;i++)out<<strvector[i].ch<<endl;out<<"最短的字符是:"<<strvector[minIndex].ch<<endl;out<<"最长的字符是:"<<strvector[maxIndex].ch<<endl;}int main(){ std::vector<struct_str> strVector;char *str = new char[N];cout<<"Input a string:"<<endl;//cin>>str;            //遇到空格就会终止读入gets_s(str,N);         //或者用gets(str);StrDeal(str,strVector);StrCmp(strVector);getchar();//int i,j,n=N;//char str[N][80]={"English","Math","Computer","Physics","Database"};//char mystring[80];////字符串排序//for(i=0;i<N;i++)//{//for(j=i;j<N;j++)//{//if(strcmp(str[i],str[j])>0)//{//strcpy(mystring,str[i]);//strcpy(str[i],str[j]);//strcpy(str[j],mystring);//}//}//}////输出排序后的字符串//cout<<"sorted strings:"<<endl;//for(i=0;i<n;i++)//cout<<str[i]<<endl;//getchar();//return 0;}////####123#4567#hnf,v.;d;\*.//bdc#abc#mln#hjk#abcd;\*.///mln#hjk#bgfl#qwert#abcgt#dkfmg.#lfkfj#fdf;\*.//English#Math#Computer#Physics#Database;\*.