To evaluate the performance of our first year CS majored students, we consider their grades of three courses only: C - C Programming Language, M - Mathematics (Calculus or Linear Algrbra), and E - English. At the mean time, we encourage students by emphasizing on their best ranks – that is, among the four ranks with respect to the three courses and the average grade, we print the best rank for each student.
For example, The grades of C, M, E and A - Average of 4 students are given as the following:
StudentID C M E A 310101 98 85 88 90 310102 70 95 88 84 310103 82 87 94 88 310104 91 91 91 91Then the best ranks for all the students are No.1 since the 1st one has done the best in C Programming Language, while the 2nd one in Mathematics, the 3rd one in English, and the last one in average.
Input Specification: Each input file contains one test case. Each case starts with a line containing 2 numbers N and M (≤2000), which are the total number of students, and the number of students who would check their ranks, respectively. Then N lines follow, each contains a student ID which is a string of 6 digits, followed by the three integer grades (in the range of [0, 100]) of that student in the order of C, M and E. Then there are M lines, each containing a student ID.
Output Specification: For each of the M students, print in one line the best rank for him/her, and the symbol of the corresponding rank, separated by a space.
The priorities of the ranking methods are ordered as A > C > M > E. Hence if there are two or more ways for a student to obtain the same best rank, output the one with the highest priority.
If a student is not on the grading list, simply output N/A. Sample Input:
5 6 310101 98 85 88 310102 70 95 88 310103 82 87 94 310104 91 91 91 310105 85 90 90 310101 310102 310103 310104 310105 999999Sample Output:
1 C 1 M 1 E 1 A 3 A N/A这题思路不是很难，有个坑就是排名的计算： 假如有一组成绩是 100 100 100 98 95 此时你得出的排名应该为1 1 1 4 5 而不是1 1 1 2 3 ，这个题目里面没有讲清，还是很坑的。
本题思路：用四个数组来分别存储四种成绩，sort排序,找出同个人在四个数组排名的最高的那个（同排名优先顺序A>C>M>E），map来存储最后的结果就可以了
AC代码：
#include<iostream> #include<algorithm> #include<vector> #include<unordered_map> using namespace std; typedef pair<string,int> PII; typedef pair<int,char> PII2; int n,m; vector<string> name; vector<PII> C,M,E,avg; int p,q,r; string na; unordered_map<string,PII2> ans; bool cmp(PII a,PII b) { return a.second>b.second; } int search(string m,vector<PII> &l) { int res=0; for(int i=0;i<l.size();i++) { if(i!=0&&l[i].second!=l[i-1].second) res=i; if(l[i].first==m) return res+1; } } int main() { cin >> n >> m; for (int i=0;i<n;i++) { cin >> na>>p>>q>>r; name.push_back(na); C.push_back({na,p}); M.push_back({na,q}); E.push_back({na,r}); avg.push_back({na,int((p+q+r)/3+0.5)}); } sort(C.begin(),C.end(),cmp); sort(M.begin(),M.end(),cmp); sort(E.begin(),E.end(),cmp); sort(avg.begin(),avg.end(),cmp); for(int i=0;i<name.size();i++) { char c='A'; int a=search(name[i],avg); if(a>search(name[i],C)) { c='C'; a=search(name[i],C); } if(a>search(name[i],M)) { c='M'; a=search(name[i],M); } if(a>search(name[i],E)) { c='E'; a=search(name[i],E); } ans[name[i]]={a,c}; } while(m--) { cin >> na; if(find(name.begin(),name.end(),na)==name.end()) printf("N/A\n"); else printf("%d %c\n",ans[na].first,ans[na].second); } return 0; }