周赛309

src/main/java/contest/y2022/m9/Week309.java

@@ -0,0 +1,87 @@
+package contest.y2022.m9;
+
+import java.util.Arrays;
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ * @author hyy
+ * @Classname Week309
+ * @Description TODO
+ * @Date 2022/9/4 10:28
+ */
+public class Week309 {
+    public static void main(String[] args) {
+        Week309 solution = new Week309();
+        solution.numberOfWays(989, 1000, 99);
+    }
+
+    public int longestNiceSubarray(int[] nums) {
+        int left = 0;
+        int num = 0;
+        int res = 1;
+        for (int i = 0; i < nums.length; i++) {
+            while (left < i && (num & nums[i]) > 0) {
+                num -= nums[left];
+                left += 1;
+            }
+            num |= nums[i];
+            res = Math.max(res, i - left + 1);
+        }
+        return res;
+    }
+
+    public int numberOfWays(int startPos, int endPos, int k) {
+        int num = k - Math.abs(endPos - startPos);
+        if (num < 0 || num % 2 == 1) {
+            return 0;
+        }
+        if (num == 0) {
+            return 1;
+        }
+        long ret = 0;
+        if (map.containsKey(endPos - 1)) {
+            Map<Integer, Integer> tmp = map.get(endPos - 1);
+            if (tmp.containsKey(k - 1)) {
+                ret += tmp.get(k - 1);
+            } else {
+                ret += numberOfWays(startPos, endPos - 1, k - 1);
+            }
+        } else {
+            ret += numberOfWays(startPos, endPos - 1, k - 1);
+        }
+        if (map.containsKey(endPos + 1)) {
+            Map<Integer, Integer> tmp = map.get(endPos + 1);
+            if (tmp.containsKey(k - 1)) {
+                ret += tmp.get(k - 1);
+            } else {
+                ret += numberOfWays(startPos, endPos + 1, k - 1);
+            }
+        } else {
+            ret += numberOfWays(startPos, endPos + 1, k - 1);
+        }
+        Map<Integer, Integer> tmp = map.getOrDefault(endPos, new HashMap<>());
+        tmp.put(k, (int) ret);
+        map.put(endPos, tmp);
+        return map.get(endPos).get(k);
+    }
+
+    Map<Integer, Map<Integer, Integer>> map = new HashMap<>();
+
+    public boolean checkDistances(String s, int[] distance) {
+        int[] arr = new int[26];
+        Arrays.fill(arr, -1);
+        for (int i = 0; i < s.length(); i++) {
+            char ch = s.charAt(i);
+            int index = ch - 'a';
+            if (arr[index] > -1) {
+                if (distance[index] != i - arr[index] - 1) {
+                    return false;
+                }
+            } else {
+                arr[index] = i;
+            }
+        }
+        return true;
+    }
+}