浙江大学PAT_甲级_1047. Student List for Course (25)

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Zhejiang University has 40000 students and provides 2500 courses. Now given the registered course list of each student, you are supposed to output the student name lists of all the courses.

Input Specification:

Each input file contains one test case. For each case, the first line contains 2 numbers: N (<=40000), the total number of students, and K (<=2500), the total number of courses. Then N lines follow, each contains a student's name (3 capital English letters
plus a one-digit number), a positive number C (<=20) which is the number of courses that this student has registered, and then followed by C course numbers. For the sake of simplicity, the courses are numbered from 1 to K.

Output Specification:

For each test case, print the student name lists of all the courses in increasing order of the course numbers. For each course, first print in one line the course number and the number of registered students, separated by a space. Then output the students'
names in alphabetical order. Each name occupies a line.
Sample Input:

10 5
ZOE1 2 4 5
ANN0 3 5 2 1
BOB5 5 3 4 2 1 5
JOE4 1 2
JAY9 4 1 2 5 4
FRA8 3 4 2 5
DON2 2 4 5
AMY7 1 5
KAT3 3 5 4 2
LOR6 4 2 4 1 5

Sample Output:

1 4
ANN0
BOB5
JAY9
LOR6
2 7
ANN0
BOB5
FRA8
JAY9
JOE4
KAT3
LOR6
3 1
BOB5
4 7
BOB5
DON2
FRA8
JAY9
KAT3
LOR6
ZOE1
5 9
AMY7
ANN0
BOB5
DON2
FRA8
JAY9
KAT3
LOR6
ZOE1

我的C++代码：

#include<iostream>
#include<string>
#include<vector>
#include<algorithm>
using namespace std;
int main()
{
vector< vector<string>> CourseInfomation;
//二维动态数组存储课程信息，CourseInfomation[i]数组记录选择i号课程的学生名字
CourseInfomation.resize(2501);//设置大小为2501
int n, k;//n学生人数，k课程数量
int i = 0, j = 0, CourseSum, CourseID;//CourseSum一位学生选择的课程总数，CourseID选择的课程编号
string name;//学生名字
scanf("%d %d", &n, &k);
for (i = 0; i < n; i++)
{
cin >> name;
scanf("%d", &CourseSum);
for (j = 0; j < CourseSum; j++)
{
scanf("%d", &CourseID);
CourseInfomation[CourseID].push_back(name);//记录学生名字，放进数组CourseInfomation[CourseID]
}
}
for (i = 1; i <= k; i++)
{
printf("%d %d\n", i, CourseInfomation[i].size());//输出选择该课程的人数
sort(CourseInfomation[i].begin(), CourseInfomation[i].end());//对学生的姓名进行排序
for (auto j : CourseInfomation[i])
{
cout << j;//输出学生姓名
printf("\n");//这里用printf，不然运行超时
}
}
//system("pause");
return 0;
}