pat

Author: flexwang

PAT/PAT_A/pat1012.cpp

@@ -0,0 +1,91 @@
+/*
+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 Algebra), 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 91
+Then 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
+
+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
+
+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
+999999
+Sample Output
+1 C
+1 M
+1 E
+1 A
+3 A
+N/A
+*/
+
+#include <unordered_map>
+#include <vector>
+#include <algorithm>
+#include <string>
+#include <iostream>
+#include <unordered_set>
+
+using namespace std;
+
+int main()
+{
+    unordered_set<string> um[4][101];
+    int n, m;
+    cin >> n >> m;
+    for (int i=0; i<n; ++i) {
+        string str;
+        int c, m, e, a;
+        cin >> str >> c >> m >> e;
+        a = (c+m+e)/3;
+        um[0][a].insert(str);
+        um[1][c].insert(str);
+        um[2][m].insert(str);
+        um[3][e].insert(str);
+    }
+    unordered_map<string, pair<int, int>> res;
+    for (int i=0; i<4; ++i) {
+        int cnt = 0;
+        for (int j=100; j>=0; --j) {
+            for (auto & s: um[i][j])
+                if (res.find(s) == res.end() 
+                    || res[s].first > cnt)
+                    res[s] = make_pair(cnt, i);
+            cnt += um[i][j].size();
+        }
+    }
+    while (m--) {
+        string q;
+        cin >> q;
+        if (res.find(q) == res.end())
+            cout << "N/A" << endl;
+        else
+            cout << res[q].first+1 << " " << "ACME"[res[q].second] << endl;
+    }
+    return 0;
+}