The Letter Carrier's Rounds

注意可能有重复的收件人。

version 1(20ms):

#include<cstdio>
#include<iostream>
#include<map>
#include<set>
#include<cstring>
#include<algorithm>
using namespace std;
const int maxn = 150,maxlen = 80;
char mes[maxlen];
map<string,string>mta;
string tf[maxn],tm[maxn];
void readmes(){int i = 0;getchar();for(;;){char c = getchar();if(c != '*'){mes[i++] = c;if(c == '\n'){int t = 5;while(t--) mes[i++] = '  ';}}else break;}mes[i] = 0;
}
int main(){int n;string a,b,t;while(cin>>t && t[0] != '*'){cin>>a>>n;while(n--){cin>>b;mta[b] = a;}}string uf,um;while(cin>>t && t[0] != '*'){int p = t.find('@',0);uf = t.substr(0,p);um = t.substr(p+1,t.length()-p+1);int cnt = 0;set<string>s;while(cin>>t && t[0] != '*'){if(s.count(t)) continue;s.insert(t);int p = t.find('@',0);tf[cnt] = t.substr(0,p);tm[cnt] = t.substr(p+1,t.length()-p+1);cnt++;}readmes();for(int i = 0;i < cnt;i++){if(!tm[i][0]) continue;cout<<"Connection between "<<um<<" and "<<tm[i]<<endl;int mark = 0;cout<<"     HELO "<<um<<endl;cout<<"     250\n";cout<<"     MAIL FROM:<"<<uf<<'@'<<um<<'>'<<endl;cout<<"     250\n";for(int j = i;j < cnt;j++){if(tm[j] != tm[i]) continue;cout<<"     RCPT TO:<"<<tf[j]<<'@'<<tm[j]<<'>'<<endl;if(mta.count(tf[j]) && mta[tf[j]] == tm[j]){mark = 1;cout<<"     250\n";}else cout<<"     550\n";if(j != i) tm[j][0] = 0;}if(mark){cout<<"     DATA\n     354\n";cout<<"     "<<mes<<".\n     250\n";}cout<<"     QUIT\n     221\n";}}return 0;
}

version 2(0ms，参考书上的代码)：

#include<iostream>
#include<map>
#include<set>
#include<vector>
#include<cstring>
#include<algorithm>
using namespace std;
void parse_addr(const string& s,string& mta,string& user){int p = s.find('@',0);user = s.substr(0,p);mta = s.substr(p + 1);
}
int main(){int n;string mta,user,mta2,user2,t;set<string>addr;while(cin>>t && t[0] != '*'){cin>>mta>>n;while(n--){cin>>user;addr.insert(user + '@' + mta);}}while(cin>>t && t[0] != '*'){parse_addr(t,mta,user);vector<string>mtas;map<string,vector<string> >users;set<string>sented;while(cin>>t && t[0] != '*'){if(sented.count(t)) continue; //消除重复的收件人sented.insert(t);parse_addr(t,mta2,user2);if(!users.count(mta2)){mtas.push_back(mta2);users[mta2] = vector<string>();}users[mta2].push_back(t);}string mes;getline(cin,t); //吃掉‘*’行的回车//在每行的开头都加五个空格，比我之前的做法简便while(getline(cin,t) && t[0] != '*') mes += "     " + t +'\n';for(int i = 0;i < mtas.size();i++){cout<<"Connection between "<<mta<<" and "<<mtas[i]<<endl;cout<<"     HELO "<<mta<<endl;cout<<"     250\n";cout<<"     MAIL FROM:<"<<user<<'@'<<mta<<">\n";cout<<"     250\n";int mark = 0;vector<string>tu = users[mtas[i]];for(int j = 0;j < tu.size();j++){cout<<"     RCPT TO:<"<<tu[j]<<">\n";if(addr.count(tu[j])) { mark = 1;cout<<"     250\n";}else cout<<"     550\n";}if(mark){cout<<"     DATA\n     354\n";cout<<mes<<"     .\n     250\n";}cout<<"     QUIT\n     221\n";}}return 0;
}