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| 1 | +package weekly; |
| 2 | + |
| 3 | +import java.util.Arrays; |
| 4 | +import java.util.Comparator; |
| 5 | +import java.util.HashMap; |
| 6 | +import java.util.HashSet; |
| 7 | +import java.util.Map; |
| 8 | +import java.util.Set; |
| 9 | + |
| 10 | +public class wk336 { |
| 11 | + //模拟 |
| 12 | + public int vowelStrings(String[] words, int left, int right) { |
| 13 | + Set<Character> set = new HashSet<>(); |
| 14 | + set.add('a'); |
| 15 | + set.add('e'); |
| 16 | + set.add('i'); |
| 17 | + set.add('o'); |
| 18 | + set.add('u'); |
| 19 | + int ans = 0; |
| 20 | + for (int i = left; i <= right; i++) { |
| 21 | + String word = words[i]; |
| 22 | + if (set.contains(word.charAt(0)) && set.contains(word.charAt(word.length() - 1))) { |
| 23 | + ans++; |
| 24 | + } |
| 25 | + } |
| 26 | + return ans; |
| 27 | + } |
| 28 | + |
| 29 | + |
| 30 | + //排序 |
| 31 | + public int maxScore(int[] nums) { |
| 32 | + Arrays.sort(nums); |
| 33 | + long sum = 0; |
| 34 | + int ans = 0; |
| 35 | + for (int i = nums.length - 1; i >= 0; i--) { |
| 36 | + sum += nums[i]; |
| 37 | + if (sum > 0) { |
| 38 | + ans++; |
| 39 | + } else { |
| 40 | + return ans; |
| 41 | + } |
| 42 | + } |
| 43 | + return ans; |
| 44 | + } |
| 45 | + |
| 46 | + //异或前缀和 |
| 47 | + public long beautifulSubarrays(int[] nums) { |
| 48 | + long ans = 0; |
| 49 | + int pre = 0; |
| 50 | + Map<Integer, Integer> map = new HashMap<>(); |
| 51 | + map.put(0, 1); |
| 52 | + for (int i = 0; i < nums.length; i++) { |
| 53 | + pre ^= nums[i]; |
| 54 | + if (map.containsKey(pre)) { |
| 55 | + Integer val = map.get(pre); |
| 56 | + ans += val; |
| 57 | + map.put(pre, val + 1); |
| 58 | + } else { |
| 59 | + map.put(pre, 1); |
| 60 | + } |
| 61 | + } |
| 62 | + return ans; |
| 63 | + } |
| 64 | + |
| 65 | + //贪心 任务尽量在后面完成 |
| 66 | + //也可以线段树 |
| 67 | + static public int findMinimumTime(int[][] tasks) { |
| 68 | + Arrays.sort(tasks, (a, b) -> a[1] != b[1] ? a[1] - b[1] : b[0] - a[0]); |
| 69 | + int ans = 0; |
| 70 | + boolean[] dp = new boolean[2001]; |
| 71 | + for (int i = 0; i < tasks.length; i++) { |
| 72 | + int[] task = tasks[i]; |
| 73 | + int start = task[0]; |
| 74 | + int end = task[1]; |
| 75 | + int duration = task[2]; |
| 76 | + for (int j = start; j <= end; j++) { |
| 77 | + if (dp[j]) { |
| 78 | + duration--; |
| 79 | + } |
| 80 | + } |
| 81 | + if (duration > 0) { |
| 82 | + for (int j = end; j >= start; j--) { |
| 83 | + if (!dp[j]) { |
| 84 | + duration--; |
| 85 | + dp[j] = true; |
| 86 | + ans++; |
| 87 | + } |
| 88 | + if (duration == 0) break; |
| 89 | + } |
| 90 | + } |
| 91 | + } |
| 92 | + return ans; |
| 93 | + } |
| 94 | + |
| 95 | + public static void main(String[] args) { |
| 96 | + findMinimumTime(new int[][]{ |
| 97 | + {2,3,1},{4,5,1},{1,5,2} |
| 98 | + }); |
| 99 | + } |
| 100 | +} |
| 101 | + |
| 102 | + |
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