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 + ;
 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 = ; i < n; i++){
         cin>>stu[i].name>>stu[i].sco>>stu[i].sch;
         if(stu[i].name[] == 'T')stu[i].sco *= 1.5;
         else if(stu[i].name[] == '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 = ;
     for(iter = school_name.begin(); iter != school_name.end(); iter++){
         string s = *iter;
         sch[id].name = s;
         schoolid[s] = id++;
     }

     for(int i = ; 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 = , tie = ;
     printf("%d\n", id);
     for(int i = ; i < id; i++){
         sch[i].sco = (int)sch[i].sco;
         if(i !=  && sch[i].sco == sch[i - ].sco){
             tie++;
         }
         else{
             rnk += tie + ;
             tie = ;
         }
         cout<<rnk<<" "<<sch[i].name<<" "<<sch[i].sco<<" "<<sch[i].num<<endl;
     }

     return ;
 }