update

1/C/Main.java

@@ -0,0 +1,54 @@
+import java.util.*;
+import java.io.*;
+
+public class Main {
+  public static void main(String[] args) throws IOException {
+    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+    int n = Integer.parseInt(br.readLine().trim());
+
+    long[][] pts = new long[n][2];
+    for (int i = 0; i < n; i++) {
+      StringTokenizer st = new StringTokenizer(br.readLine());
+      pts[i][0] = Math.abs(Long.parseLong(st.nextToken()));
+      pts[i][1] = Math.abs(Long.parseLong(st.nextToken()));
+    }
+
+    Arrays.sort(pts, (p, q) -> p[0] != q[0] ? Long.compare(q[0], p[0]) : Long.compare(q[1], p[1]));
+
+    List<long[]> front = new ArrayList<>();
+    long maxY = 0;
+    int i = 0;
+    while (i < n) {
+      int j = i;
+      long curX = pts[i][0];
+      long curMaxY = 0;
+      while (j < n && pts[j][0] == curX) {
+        curMaxY = Math.max(curMaxY, pts[j][1]);
+        j++;
+      }
+      if (curMaxY > maxY) {
+        front.add(new long[] { curX, curMaxY });
+        maxY = curMaxY;
+      }
+      i = j;
+    }
+
+    int m = front.size();
+    long[] dp = new long[m + 1];
+    dp[m] = 0;
+
+    for (int ii = m - 1; ii >= 0; ii--) {
+      long a = front.get(ii)[0];
+      long b = 0;
+      dp[ii] = Long.MAX_VALUE;
+      for (int jj = ii; jj < m; jj++) {
+        b = Math.max(b, front.get(jj)[1]);
+        long area = 4L * a * b;
+        long total = area + dp[jj + 1];
+        dp[ii] = Math.min(dp[ii], total);
+      }
+    }
+
+    System.out.println(dp[0]);
+  }
+}