[김주현] 4주차 문제풀이

김주현/실패율.java

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+import java.util.*;
+
+class Solution {
+    static int N, M; // 스테이지 수, 사람 수
+    static int[] stages;
+    static int[] users;
+    static int[] passedUsers;
+
+    static class Stage implements Comparable<Stage> {
+        int stage;
+        int numerator;
+        int denominator;
+
+        public Stage(int stage, int numerator, int denominator) {
+            this.stage = stage;
+            this.numerator = numerator;
+            this.denominator = denominator;
+        }
+
+        @Override
+        public int compareTo(Stage o) {
+            if ( this.denominator == 0 || o.denominator == 0 ) {
+                if (this.denominator == o.denominator ) {
+                    return this.stage - o.stage;
+                } else {
+                    return o.denominator - this.denominator;
+                }
+            }
+
+            long comp = (long)o.numerator*this.denominator - (long)this.numerator*o.denominator;
+            if (comp > 0) return 1;
+            if (comp < 0) return -1;
+            return this.stage - o.stage;
+        }
+    }
+
+    public int[] solution(int n, int[] s) {
+        N = n;
+        stages = s;
+        M = s.length;
+
+        users = new int[n+2];
+        passedUsers = new int[n+2];
+
+        countUsers();
+        countPassedUsers();
+
+        Stage[] res = new Stage[N];
+        for (int i=1; i<=N; i++) {
+            res[i-1] = new Stage(i, users[i], passedUsers[i]);
+        }
+
+        Arrays.sort(res);
+
+        int[] answer = new int[N];
+        for (int i=0; i<N; i++) {
+            answer[i] = res[i].stage;
+        }
+
+        return answer;
+    }
+
+    public void countUsers() {
+        for (int stage: stages) {
+            users[stage]++;
+        }
+    }
+
+    public void countPassedUsers() {
+        passedUsers[N+1] = users[N+1];
+        for (int i=N; i>=1; i--) {
+            passedUsers[i] = users[i] + passedUsers[i+1];
+        }
+    }
+}