CS106L assignment2 Marriage Pact

给一个姓名表，取首字母作匹配，将姓名表存入set里面 ，然后从set里遍历缩写，和函数给出的name对应的缩写相同的话则放入队列里（这里队列里存的string指针），队列是可能匹配的人，然后随一个出来

用指针的话 对于string可能很长，指针则只会操作地址而非字符串，加快速度，空间时间上都更好 引用的都是同一份数据

/*
 * CS106L Assignment 2: Marriage Pact
 * Created by Haven Whitney with modifications by Fabio Ibanez & Jacob Roberts-Baca.
 *
 * Welcome to Assignment 2 of CS106L! Please complete each STUDENT TODO
 * in this file. You do not need to modify any other files.
 *
 */

#include <fstream>
#include <iostream>
#include <queue>
#include <set>
#include <string>
#include <unordered_set>
#include <random>

std::string kYourName = "XuanRui Liu"; // Don't forget to change this!

/**
 * Takes in a file name and returns a set containing all of the applicant names as a set.
 *
 * @param filename  The name of the file to read.
 *                  Each line of the file will be a single applicant's name.
 * @returns         A set of all applicant names read from the file.
 *
 * @remark Feel free to change the return type of this function (and the function
 * below it) to use a `std::unordered_set` instead. If you do so, make sure
 * to also change the corresponding functions in `utils.h`.
 */
std::set<std::string> get_applicants(std::string filename) {
  // STUDENT TODO: Implement this function.
  
  std::set<std::string> cts;
  
  std::ifstream in(filename);
  std::string tmp;
  while(std::getline(in, tmp)) {
    if (tmp.empty()) {
            continue;
        }
    cts.insert(tmp);
    //std::cout<<"hello";
  }
  in.close();
  return cts;

}

/**
 * Takes in a set of student names by reference and returns a queue of names
 * that match the given student name.
 *
 * @param name      The returned queue of names should have the same initials as this name.
 * @param students  The set of student names.
 * @return          A queue containing pointers to each matching name.
 */
std::queue<const std::string*> find_matches(std::string name, std::set<std::string>& students) {
  // STUDENT TODO: Implement this function.
  std::queue<const std::string*> tmp;
  char a = name[0], b;
  for(int i = 1 ; i < name.size(); i++) {
    if(name[i] >= 'A' && name[i] <= 'Z')  {
      b = name[i];
    }
  }
  
  char tmpa, tmpb;
  for(auto x : students) {
    //std::cout<<x.size()<<std::endl;
    tmpa = x[0];
    for(int i = 1; i < x.size(); i++) {
      if(x[i] >= 'A' && x[i] <= 'Z')  {
      tmpb = x[i];
    }
    }
    if(a == tmpa && b == tmpb) tmp.push(&x);
  }
  return tmp;
}

/**
 * Takes in a queue of pointers to possible matches and determines the one true match!
 *
 * You can implement this function however you'd like, but try to do something a bit
 * more complicated than a simple `pop()`.
 *
 * @param matches The queue of possible matches.
 * @return        Your magical one true love.
 *                Will return "NO MATCHES FOUND." if `matches` is empty.
 */
std::string get_match(std::queue<const std::string*>& matches) {
  // STUDENT TODO: Implement this function.
  const std::string nfd = "NO MATCHES FOUND.";
  if(matches.empty()) return nfd;
  std::random_device rd;
  std::mt19937 gen(rd());
  std::uniform_int_distribution<> dis(0, matches.size() - 1); 
  int rdm = dis(gen);
  
  while(rdm--) {
    matches.pop();
  }
  
  return *(matches.front());
}

/* #### Please don't remove this line! #### */
#include "autograder/utils.hpp"