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package class46;
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// 本题测试链接 : https://leetcode.com/problems/remove-boxes/
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public class Code02_RemoveBoxes {
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// arr[L...R]消除，而且前面跟着K个arr[L]这个数
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// 返回：所有东西都消掉，最大得分
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public static int func1(int[] arr, int L, int R, int K) {
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if (L > R) {
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return 0;
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}
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int ans = func1(arr, L + 1, R, 0) + (K + 1) * (K + 1);
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// 前面的K个X，和arr[L]数，合在一起了，现在有K+1个arr[L]位置的数
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for (int i = L + 1; i <= R; i++) {
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if (arr[i] == arr[L]) {
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ans = Math.max(ans, func1(arr, L + 1, i - 1, 0) + func1(arr, i, R, K + 1));
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}
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}
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return ans;
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}
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public static int removeBoxes1(int[] boxes) {
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int N = boxes.length;
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int[][][] dp = new int[N][N][N];
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int ans = process1(boxes, 0, N - 1, 0, dp);
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return ans;
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}
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public static int process1(int[] boxes, int L, int R, int K, int[][][] dp) {
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if (L > R) {
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return 0;
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}
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if (dp[L][R][K] > 0) {
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return dp[L][R][K];
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}
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int ans = process1(boxes, L + 1, R, 0, dp) + (K + 1) * (K + 1);
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for (int i = L + 1; i <= R; i++) {
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if (boxes[i] == boxes[L]) {
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ans = Math.max(ans, process1(boxes, L + 1, i - 1, 0, dp) + process1(boxes, i, R, K + 1, dp));
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}
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}
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dp[L][R][K] = ans;
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return ans;
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}
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public static int removeBoxes2(int[] boxes) {
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int N = boxes.length;
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int[][][] dp = new int[N][N][N];
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int ans = process2(boxes, 0, N - 1, 0, dp);
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return ans;
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}
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public static int process2(int[] boxes, int L, int R, int K, int[][][] dp) {
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if (L > R) {
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return 0;
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}
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if (dp[L][R][K] > 0) {
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return dp[L][R][K];
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}
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// 找到开头，
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// 1,1,1,1,1,5
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// 3 4 5 6 7 8
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// !
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int last = L;
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while (last + 1 <= R && boxes[last + 1] == boxes[L]) {
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last++;
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}
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// K个1 (K + last - L) last
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int pre = K + last - L;
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int ans = (pre + 1) * (pre + 1) + process2(boxes, last + 1, R, 0, dp);
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for (int i = last + 2; i <= R; i++) {
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if (boxes[i] == boxes[L] && boxes[i - 1] != boxes[L]) {
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ans = Math.max(ans, process2(boxes, last + 1, i - 1, 0, dp) + process2(boxes, i, R, pre + 1, dp));
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}
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}
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dp[L][R][K] = ans;
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return ans;
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}
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}
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