[20260226] BOJ / G5 / 두개의 탑 / 이인희

LiiNi-coder/202602/26 BOJ 두개의 탑.md

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+```java
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+
+public class Main {
+	static long[] Prefix;
+	static long Total;
+
+	public static void main(String[] args) throws IOException {
+		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+		int N = Integer.parseInt(br.readLine().trim());
+		long[] dist = new long[N];
+		for(int i = 0; i < N; i++) {
+			dist[i] = Long.parseLong(br.readLine());
+		}
+
+		//원형 -> 배열을 2배
+		Prefix = new long[2*N + 1];
+		for(int i = 0; i < 2 * N; i++) {
+			Prefix[i + 1] = Prefix[i] + dist[i % N];
+		}
+		Total = Prefix[N];
+		long answer = 0;
+		for(int i = 0; i < N; i++) {
+			int l = i;
+			int r = i + N;
+			while(l + 1 < r) {
+				int mid = (l+r) / 2;
+				if(check(i, mid) == check(i, l)) {
+					l = mid;
+				}else {
+					r = mid;
+				}
+			}
+			long clockwise = Prefix[l] - Prefix[i];
+			answer = Math.max(answer, clockwise);
+		}
+
+		System.out.println(answer);
+	}
+
+	static boolean check(int i, int mid) {
+		return (Prefix[mid] - Prefix[i]<= Total/2);
+	}
+}
+
+```