【PAT】甲级1028 List Sorting (25 分)

题目

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.

测试用例

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

题解

#include<bits/stdc++.h>
using namespace std;

int n,c;  // 总共输入三行

// 定义学生信息结构体
struct NODE
{
    int no;
    string name;
    int score;
};

int cmp(NODE a, NODE b)
{
    if(c == 1)
    {
        return a.no < b.no;// 从小到大顺序
    }
    else if(c == 2)
    {   // If there are several students who have the same name or grade, they must be sorted according to their ID's in increasing order.
        if(a.name != b.name)
        {
            return a.name < b.name;
        }
        else{
            return a.no < b.no;
        }
    }
    else if(c == 3){
        if(a.score != b.score)
        {
            return a.score < b.score;
        }
        else{
            return a.no < b.no;
        }
    }
}

int main()
{
    cin>>n>>c;
    vector<NODE> node(n); // 定义一个数组存储三个学生的结构体

    // 读入学生信息
    for(int i = 0; i < n; i++)
    {
        cin>>node[i].no>>node[i].name>>node[i].score;
    }

    // 排序  注意第三个参数：定义排序的规则
    sort(node.begin(),node.end(),cmp);

    for(int i = 0; i < n; i++)
    {
        printf("%06d %s %d\n",node[i].no,node[i].name.c_str(),node[i].score);
    }

    return 0;
}