1036. Boys vs Girls (25)

题目例如以下：

This time you are asked to tell the difference between the lowest grade of all the male students and the highest grade of all the female students.

Input Specification:

Each input file contains one test case. Each case contains a positive integer N, followed by N lines of student information. Each line contains a student's name, gender, ID and grade, separated by a space, where name and ID are strings of no more than 10 characters with no space, gender is either F (female) or M (male), and grade is an integer between 0 and 100. It is guaranteed that all the grades are distinct.

Output Specification:

For each test case, output in 3 lines. The first line gives the name and ID of the female student with the highest grade, and the second line gives that of the male student with the lowest grade. The third line gives the difference grade_F-grade_M. If one such kind of student is missing, output "Absent" in the corresponding line, and output "NA" in the third line instead.

Sample Input 1:

3
Joe M Math990112 89
Mike M CS991301 100
Mary F EE990830 95

Sample Output 1:

Mary EE990830
Joe Math990112
6

Sample Input 2:

1
Jean M AA980920 60

Sample Output 2:

Absent
Jean AA980920
NA

题目非常easy，仅仅须要定义Person结构体存储信息。建立男、女两个vector容器分别容纳各条记录，然后依照题目要求排序。最后依照要求输出就可以，注意在输出时推断是否男、女容器都不空。有空的要输出Absent和NA。

#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;

struct Person{

    string name;
    char gender;
    string ID;
    int grade;

    Person(string _n, char _gen, string _id, int _grade) : name(_n), gender(_gen), ID(_id), grade(_grade) {}

};

int compareF(Person a, Person b){
    return a.grade > b.grade;
}

int compareM(Person a, Person b){
    return a.grade < b.grade;
}

int main()
{
    vector<Person> males, females;
    int N;
    cin >> N;
    string name,id;
    char gender;
    int score;
    for(int i = 0; i < N; i++){
        cin >> name >> gender >> id >> score;
        if(gender == 'M'){
            males.push_back(Person(name,gender,id,score));
        }else{
            females.push_back(Person(name,gender,id,score));
        }
    }
    Person *m = NULL;
    Person *fm = NULL;
    if(males.size() != 0){
        sort(males.begin(),males.end(),compareM);
        m = &males[0];
    }
    if(females.size() != 0){
        sort(females.begin(),females.end(),compareF);
        fm = &females[0];
    }

    if(fm != NULL){
        cout << fm->name << " " << fm->ID << endl;
    }else{
        cout << "Absent" << endl;
    }
    if(m != NULL){
        cout << m->name << " " << m->ID << endl;
    }else{
        cout << "Absent" << endl;
    }
    if(fm != NULL && m != NULL){
        cout << (fm->grade - m->grade) << endl;
    }else{
        cout << "NA" << endl;
    }

    return 0;
}