学步园

题目：http://pat.zju.edu.cn/contests/pat-a-practise/1028

题解：

模拟题。写三个比较函数即可。

代码：

#include<cstdio>
#include<cstring>
#include<cmath>
#include<string>
#include<set>
#include<vector>
#include<algorithm>
using namespace std;
struct student
{
    char id[15];
    char name[15];
    int grade;
} stu[100005];
bool cmp1(const struct student &a,const struct student &b)
{
    return strcmp(a.id,b.id)<0;
}
bool cmp2(const struct student &a,const struct student &b)
{
    return strcmp(a.name,b.name)<0?(true):(strcmp(a.name,b.name)!=0?(false):(strcmp(a.id,b.id)<0));
}
bool cmp3(const struct student &a,const struct student &b)
{
    return a.grade<b.grade?(true):(a.grade!=b.grade?(false):(strcmp(a.id,b.id)<0));
}
int main()
{
    int n,c;
    scanf("%d%d",&n,&c);
    for(int i=0;i<n;++i)
        scanf("%s%s%d",stu[i].id,stu[i].name,&stu[i].grade);
    if(c==1)
        sort(stu,stu+n,cmp1);
    else if(c==2)
        sort(stu,stu+n,cmp2);
    else
        sort(stu,stu+n,cmp3);
    for(int i=0;i<n;++i)
        printf("%s %s %d\n",stu[i].id,stu[i].name,stu[i].grade);
    return 0;
}

来源：http://blog.csdn.net/acm_ted/article/details/20162035