PAT甲级1028(列表排序)

1028 List Sorting (25 point(s))

  Excel can sort records according to any column. Now you are supposed to imitate this function.

Input Specification:
  Each input file contains one test case. For each case, the first line contains two integers N (≤10^​5) and C, where N is the number of records and C is the column that you are supposed to sort the records with. Then N lines follow, each contains a record of a student. A student’s record consists of his or her distinct ID (a 6-digit number), name (a string with no more than 8 characters without space), and grade (an integer between 0 and 100, inclusive).

Output Specification:
  For each test case, output the sorting result in N lines. That is, if C = 1 then the records must be sorted in increasing order according to ID’s; if C = 2 then the records must be sorted in non-decreasing order according to names; and if C = 3 then the records must be sorted in non-decreasing order according to grades. If there are several students who have the same name or grade, they must be sorted according to their ID’s in increasing order.

Sample Input 1:

3 1
000007 James 85
000010 Amy 90
000001 Zoe 60

Sample Output 1:

000001 Zoe 60
000007 James 85
000010 Amy 90

Sample Input 2:

4 2
000007 James 85
000010 Amy 90
000001 Zoe 60
000002 James 98

Sample Output 2:

000010 Amy 90
000002 James 98
000007 James 85
000001 Zoe 60

Sample Input 3:

4 3
000007 James 85
000010 Amy 90
000001 Zoe 60
000002 James 90

Sample Output 3:

000001 Zoe 60
000007 James 85
000002 James 90
000010 Amy 90

题目大意

  给出N条信息，按照要求进行排序：1表示按id非递减排序；2表示按照name非递减排序，如果相等则按id非递减排序；3表示按照grade非递减排序，如果相等则按照id非递减排序

解题思路

  先构造结构体数组，存储id，name，grade，再分别构造三个满足上述排序要求的比较方式，输入数据后，依照要求对结构体数组进行排序，最后直接输出即可

代码

#define _CRT_SECURE_NO_WARNINGS
#include 
#include 
#include 
using namespace std;

struct info {
     
	int id;
	char name[10];
	int grade;
}Stu[100005];

bool cmp1(info a, info b) {
     //按学id递增排序
	return a.id < b.id;
}

bool cmp2(info a, info b) {
     //按name递增排序，如果name相等，则按id递增排序
	if (strcmp(a.name, b.name) != 0) return strcmp(a.name, b.name) < 0;
	else return a.id < b.id;
}

bool cmp3(info a, info b) {
     //按grade排序，如果grade相等，则按id递增排序
	if (a.grade != b.grade) return a.grade < b.grade;
	else return a.id < b.id;
}

int main()
{
     
	int N, i, C;
	int ret = scanf("%d %d", &N, &C);
	for (i = 0; i < N; ++i) {
     
		ret = scanf("%d %s %d", &Stu[i].id, Stu[i].name, &Stu[i].grade);
	}
	if (C == 1) {
     
		sort(Stu, Stu + i, cmp1);
	} else if (C == 2) {
     
		sort(Stu, Stu + i, cmp2);
	} else {
     
		sort(Stu, Stu + i, cmp3);
	}
	for (i = 0; i < N; ++i) {
     
		printf("%06d %s %d\n", Stu[i].id, Stu[i].name, Stu[i].grade);
	}
	return 0;
}