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 Nlines 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 <stdio.h>
#include <algorithm>
#include <string>
#include <iostream>
using namespace std;
const int maxn=;
struct stu{
string id;
string name;
int grade;
}students[maxn];
bool cmp1(stu s1,stu s2){
return s1.id<s2.id;
}
bool cmp2(stu s1,stu s2){
if(s1.name==s2.name) return s1.id<s2.id;
else return s1.name<s2.name;
}
bool cmp3(stu s1,stu s2){
if(s1.grade==s2.grade) return s1.id<s2.id;
else return s1.grade<s2.grade;
}
int main(){
int n,c;
scanf("%d %d",&n,&c);
for(int i=;i<n;i++){
cin>>students[i].id>>students[i].name>>students[i].grade;
}
if(c==){
sort(students,students+n,cmp1);
}
else if(c==){
sort(students,students+n,cmp2);
}
else if(c==){
sort(students,students+n,cmp3);
}
for(int i=;i<n;i++){
printf("%s %s %d\n",students[i].id.c_str(),students[i].name.c_str(),students[i].grade);
}
}
注意点：很简单的排序题，但是最后一个测试点会超时，原因是cout很慢，一开始以为是sort很慢，想是不是要用priority_queue，发现一样超时。然后把id改成int试了试还是超时，百度了一下，发现人家也都是sort做的唯一不同输出name也用printf。最后果然是cout速度太慢，printf输出string要用c_str。