[20251010] BOJ / G4 / 공유기 설치 / 강신지

ksinji/202510/10 BOJ G4 공유기 설치.md

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+```java
+import java.io.*;
+import java.util.*;
+
+public class Main {
+    static int N, C;
+    static int[] house;
+
+    public static void main(String[] args) throws Exception {
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        StringTokenizer st = new StringTokenizer(br.readLine());
+        N = Integer.parseInt(st.nextToken());
+        C = Integer.parseInt(st.nextToken());
+
+        house = new int[N];
+        for (int i = 0; i < N; i++) house[i] = Integer.parseInt(br.readLine());
+        Arrays.sort(house);
+
+        int lo = 1; // 최소 간격
+        int hi = house[N - 1] - house[0]; // 최대 간격
+        int ans = 0;
+
+        while (lo <= hi) {
+            int mid = lo + (hi - lo) / 2;
+            if (canPlace(mid)) { // mid 간격으로 C개 설치 가능
+                ans = mid;
+                lo = mid + 1;
+            } else {
+                hi = mid - 1;
+            }
+        }
+
+        System.out.println(ans);
+    }
+
+    // dist 간격을 유지하며 C개 설치 가능한지
+    static boolean canPlace(int dist) {
+        int count = 1; // 첫 집에 설치
+        int last = house[0];
+        for (int i = 1; i < N; i++) {
+            if (house[i] - last >= dist) {
+                count++;
+                last = house[i];
+                if (count >= C) return true;
+            }
+        }
+        return false;
+    }
+}
+```