1028 List Sorting (25分)

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 (≤105) 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

#include<iostream>
#include<algorithm>
#include<vector>
using namespace std;
typedef struct students{
    int number;
    string name;
    int score;
}st;
int cmp1(st p1,st p2){
    return p1.number<p2.number;
}
int cmp2(st p1,st p2){
    if(p1.name == p2.name){
        return p1.number<p2.number;
    }else{
        return p1.name<p2.name;
    }
    return 0;
}
int cmp3(st p1,st p2){
    if(p1.score == p2.score){
        return p1.number<p2.number;
    }else{
        return p1.score<p2.score;
    }
    return 0;
}
int main(){
    vector<st> list;
    int m,n;
    cin>>m>>n;
    st node;
    for(int i=0;i<m;i++){
        cin>>node.number>>node.name>>node.score;
        list.push_back(node);
    }
    if(n==1){
        sort(list.begin(),list.end(),cmp1); 
    }
    else if(n==2){
        sort(list.begin(),list.end(),cmp2);
    }
    else{
        sort(list.begin(),list.end(),cmp3);
    }
    for(int i=0;i<m;++i){
        printf("%06d ",list[i].number);
        cout<<list[i].name;
        printf(" %d\n",list[i].score);
    }
    return 0;
}