modify code

src/class46/Code02_RemoveBoxes.java

@@ -3,24 +3,54 @@ package class46;
 // 本题测试链接 : https://leetcode.com/problems/remove-boxes/
 public class Code02_RemoveBoxes {
 
-	public static int removeBoxes(int[] boxes) {
+	public static int removeBoxes1(int[] boxes) {
 		int N = boxes.length;
 		int[][][] dp = new int[N][N][N];
-		int ans = process(boxes, 0, N - 1, 0, dp);
+		int ans = process1(boxes, 0, N - 1, 0, dp);
 		return ans;
 	}
 
-	public static int process(int[] boxes, int L, int R, int K, int[][][] dp) {
+	public static int process1(int[] boxes, int L, int R, int K, int[][][] dp) {
 		if (L > R) {
 			return 0;
 		}
 		if (dp[L][R][K] > 0) {
 			return dp[L][R][K];
 		}
-		int ans = process(boxes, L + 1, R, 0, dp) + (K + 1) * (K + 1);
+		int ans = process1(boxes, L + 1, R, 0, dp) + (K + 1) * (K + 1);
 		for (int i = L + 1; i <= R; i++) {
 			if (boxes[i] == boxes[L]) {
-				ans = Math.max(ans, process(boxes, L + 1, i - 1, 0, dp) + process(boxes, i, R, K + 1, dp));
+				ans = Math.max(ans, process1(boxes, L + 1, i - 1, 0, dp) + process1(boxes, i, R, K + 1, dp));
+			}
+		}
+		dp[L][R][K] = ans;
+		return ans;
+	}
+
+	public static int removeBoxes2(int[] boxes) {
+		int N = boxes.length;
+		int[][][] dp = new int[N][N][N];
+		int ans = process2(boxes, 0, N - 1, 0, dp);
+		return ans;
+	}
+
+	public static int process2(int[] boxes, int L, int R, int K, int[][][] dp) {
+		if (L > R) {
+			return K * K;
+		}
+		if (dp[L][R][K] > 0) {
+			return dp[L][R][K];
+		}
+		int ans = 0;
+		int last = L;
+		while (last + 1 <= R && boxes[last + 1] == boxes[L]) {
+			last++;
+		}
+		int pre = K + last - L;
+		ans = (pre + 1) * (pre + 1) + process2(boxes, last + 1, R, 0, dp);
+		for (int i = last + 2; i <= R; i++) {
+			if (boxes[i] == boxes[L] && boxes[i - 1] != boxes[L]) {
+				ans = Math.max(ans, process2(boxes, last + 1, i - 1, 0, dp) + process2(boxes, i, R, pre + 1, dp));
 			}
 		}
 		dp[L][R][K] = ans;