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package class35;
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// 来自网易
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// 给定一个正数数组arr，表示每个小朋友的得分
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// 任何两个相邻的小朋友，如果得分一样，怎么分糖果无所谓，但如果得分不一样，分数大的一定要比分数少的多拿一些糖果
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// 假设所有的小朋友坐成一个环形，返回在不破坏上一条规则的情况下，需要的最少糖果数
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public class Code05_CircleCandy {
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public static int minCandy(int[] arr) {
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if (arr == null || arr.length == 0) {
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return 0;
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}
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if (arr.length == 1) {
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return 1;
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}
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int n = arr.length;
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int minIndex = 0;
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for (int i = 0; i < n; i++) {
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if (arr[i] <= arr[lastIndex(i, n)] && arr[i] <= arr[nextIndex(i, n)]) {
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minIndex = i;
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break;
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}
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}
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int[] nums = new int[n + 1];
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for (int i = 0; i <= n; i++, minIndex = nextIndex(minIndex, n)) {
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nums[i] = arr[minIndex];
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}
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int[] left = new int[n + 1];
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left[0] = 1;
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for (int i = 1; i <= n; i++) {
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left[i] = nums[i] > nums[i - 1] ? (left[i - 1] + 1) : 1;
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}
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int[] right = new int[n + 1];
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right[n] = 1;
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for (int i = n - 1; i >= 0; i--) {
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right[i] = nums[i] > nums[i + 1] ? (right[i + 1] + 1) : 1;
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}
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int ans = 0;
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for (int i = 0; i < n; i++) {
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ans += Math.max(left[i], right[i]);
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}
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return ans;
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}
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public static int nextIndex(int i, int n) {
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return i == n - 1 ? 0 : (i + 1);
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}
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public static int lastIndex(int i, int n) {
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return i == 0 ? (n - 1) : (i - 1);
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}
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public static void main(String[] args) {
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int[] arr = { 3, 4, 2, 3, 2 };
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System.out.println(minCandy(arr));
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}
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}
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