PAT甲级1141 Ranking of Institutions

题目：https://pintia.cn/problem-sets/994805342720868352/problems/994805344222429184

题意：

给定几个学生的PAT分数和学校，给这些学校学生的PAT总分排序。

思路：

库函数tolower()和toupper()可以分别把字符串转换为都是小写字母和都是大写字母。

这道题要注意的是，因为是加权的总分，算的时候应该用double。但是题目中有说，总分取加权之后的整数部分，全部加完后要转成int进行比较。

//#include<bits/stdc++>
#include<stdio.h>
#include<iostream>
#include<algorithm>
#include<cstring>
#include<stdlib.h>
#include<queue> 
#include<map>
#include<stack>
#include<set>

#define LL long long
#define ull unsigned long long
#define inf 0x7f7f7f7f 

using namespace std;

const int maxn = 1e5 + 5;
int n;
struct school{
    string name;
    int num;
    double sco;
    int rnk;
}sch[maxn];
set<string>school_name;
set<string>::iterator iter;
map<string, int>schoolid;

bool cmp(school &a, school &b)
{
    if((int)a.sco == (int)b.sco)
        if(a.num == b.num)return a.name < b.name;
        else return a.num < b.num;
    else return (int)a.sco > (int)b.sco;
}

struct student{
    string name;
    double sco;
    string sch;
}stu[maxn];

int main()
{
    scanf("%d", &n);
    for(int i = 0; i < n; i++){
        cin>>stu[i].name>>stu[i].sco>>stu[i].sch;
        if(stu[i].name[0] == 'T')stu[i].sco *= 1.5;
        else if(stu[i].name[0] == 'B')stu[i].sco /= 1.5;
        transform(stu[i].sch.begin(), stu[i].sch.end(), stu[i].sch.begin(), ::tolower);
        school_name.insert(stu[i].sch);
    }
    int id = 0;
    for(iter = school_name.begin(); iter != school_name.end(); iter++){
        string s = *iter;
        sch[id].name = s;
        schoolid[s] = id++;
    }
    
    for(int i = 0; i < n; i++){
        int sid = schoolid[stu[i].sch];
        sch[sid].num++;
        sch[sid].sco += stu[i].sco;
    }
    
    sort(sch, sch + id, cmp);
    int rnk = 0, tie = 0;
    printf("%d
", id);
    for(int i = 0; i < id; i++){
        sch[i].sco = (int)sch[i].sco;
        if(i != 0 && sch[i].sco == sch[i - 1].sco){
            tie++;
        }
        else{
            rnk += tie + 1;
            tie = 0;
        }
        cout<<rnk<<" "<<sch[i].name<<" "<<sch[i].sco<<" "<<sch[i].num<<endl;
    }
    
    return 0;    
}