[20251016] BOJ / G3 / 구조대 / 한종욱

Author: Ukj0ng

Ukj0ng/202510/16 BOJ G3 구조대.md

@@ -0,0 +1,87 @@
+```
+import java.io.*;
+import java.util.*;
+
+public class Main {
+    private static BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+    private static BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));
+    private static List<int[]> events;
+    private static Map<Integer, Integer> teamCount;
+    private static int N, M;
+    public static void main(String[] args) throws IOException {
+        init();
+        int answer = solve();
+
+        bw.write(answer + "\n");
+        bw.flush();
+        bw.close();
+        br.close();
+    }
+
+    private static void init() throws IOException {
+        StringTokenizer st = new StringTokenizer(br.readLine());
+        N = Integer.parseInt(st.nextToken());
+        M = Integer.parseInt(st.nextToken());
+
+        events = new ArrayList<>();
+
+        for (int i = 0; i < N; i++) {
+            st = new StringTokenizer(br.readLine());
+            int l = Integer.parseInt(st.nextToken());
+            int r = Integer.parseInt(st.nextToken());
+            int team = Integer.parseInt(st.nextToken());
+
+            int startS = Math.max(0, l-M);
+            int endS = r;
+
+            events.add(new int[]{startS, 0, team});
+            events.add(new int[]{endS, 1, team});
+        }
+
+        Collections.sort(events, (o1, o2) -> Integer.compare(o1[0], o2[0]));
+
+        teamCount = new HashMap<>();
+    }
+
+    private static int solve() {
+        int answer = 0;
+        int prevS = -1;
+        int validTeams = 0;
+
+        for (int[] element : events) {
+            if (element[0] != prevS && prevS >= 0) {
+                answer = Math.max(answer, validTeams);
+            }
+
+            int team = element[2];
+            int oldCount = teamCount.getOrDefault(team, 0);
+
+            if (element[1] == 0) {
+                int newCount = oldCount + 1;
+                teamCount.put(team, newCount);
+
+                if (oldCount == 1 && newCount == 2) {
+                    validTeams++;
+                }
+            } else {
+                int newCount = oldCount - 1;
+
+                if (oldCount == 2 && newCount == 1) {
+                    validTeams--;
+                }
+
+                if (newCount == 0) {
+                    teamCount.remove(team);
+                } else {
+                    teamCount.put(team, newCount);
+                }
+            }
+
+            prevS = element[0];
+        }
+
+        answer = Math.max(answer, validTeams);
+        return answer;
+    }
+}
+```