weekly contest 382

Author: ZLBer

Diff for: README.md

@@ -4,6 +4,9 @@ Record leetcode contest and ideas every week, and encourage yourself to think mo
 
 leetcode url: <https://leetcode.cn/u/cctest/>
 
+
+
+* 🐼 [weekly contest 381](src/main/java/weekly/wk381.java)     遍历 | 枚举 | 数学 |  贪心
 * 🐼 [weekly contest 381](src/main/java/weekly/wk381.java)     贪心 | 贪心 | floyd
 * 🐼 [weekly contest 380](src/main/java/weekly/wk380.java)     遍历 | kmp | 二分+数位dp | kmp+二分
 * 🐼 [weekly contest 379](src/main/java/weekly/wk379.java)     遍历 | 贪心 | 分类

Diff for: src/main/java/weekly/wk341.java

@@ -1,7 +1,5 @@
 package weekly;
 
-import sun.security.krb5.internal.APRep;
-
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.HashMap;

Diff for: src/main/java/weekly/wk356.java

@@ -1,6 +1,5 @@
 package weekly;
 
-import com.sun.xml.internal.xsom.impl.scd.Iterators;
 
 import java.util.Arrays;
 import java.util.HashMap;

Diff for: src/main/java/weekly/wk382.java

@@ -0,0 +1,110 @@
+package weekly;
+
+import java.util.Arrays;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Map;
+import java.util.Set;
+
+public class wk382 {
+    //遍历
+    public int countKeyChanges(String s) {
+        int ans = 0;
+        for (int i = 1; i < s.length(); i++) {
+            if (Character.toLowerCase(s.charAt(i)) != Character.toLowerCase(s.charAt(i - 1))) {
+                ans++;
+            }
+        }
+        return ans;
+    }
+
+
+    //枚举
+    public int maximumLength(int[] nums) {
+        Map<Integer, Integer> counter = new HashMap<>();
+        for (int num : nums) {
+            counter.put(num, counter.getOrDefault(num, 0) + 1);
+        }
+        Set<Integer> set = new HashSet<>();
+        Integer ones = counter.getOrDefault(1, 0);
+        int res = ones % 2 == 1 ? ones : ones - 1;
+        Arrays.sort(nums);
+        for (int i = 0; i < nums.length; i++) {
+            int ans = 0;
+            int num = nums[i];
+            if (num == 1) continue;
+            if (set.contains(num)) continue;
+            while (true) {
+                Integer count = counter.get(num);
+                set.add(num);
+                if (count == null) {
+                    ans -= 1;
+                    break;
+                } else if (count >= 2) {
+                    ans += 2;
+                } else if (count == 1) {
+                    ans += 1;
+                    break;
+                }
+                num *= num;
+            }
+            res = Math.max(ans, res);
+        }
+        return res;
+    }
+
+
+    //找规律
+    public long flowerGame(int n, int m) {
+        long na = 0, nb = 0;
+        if (n % 2 == 1) {
+            na = (n + 1) / 2;
+            nb = n / 2;
+        } else {
+            na = (n) / 2;
+            nb = n / 2;
+        }
+
+        long ma = 0, mb = 0;
+        if (m % 2 == 1) {
+            ma = (m + 1) / 2;
+            mb = m / 2;
+        } else {
+            ma = m / 2;
+            mb = m / 2;
+        }
+      long res=0;
+       res+= na*mb+nb*ma;
+       return res;
+    }
+
+    // 试填法
+    public int minOrAfterOperations(int[] nums, int k) {
+        int ans = 0;
+        int mask = 0;
+        for (int b = 29; b >= 0; b--) {
+            mask |= 1 << b;
+            int cnt = 0; // 操作次数
+            int and = -1; // -1 的二进制全为 1
+            for (int x : nums) {
+                and &= x & mask;
+                if (and != 0) {
+                    cnt++; // 合并 x，操作次数加一
+                } else {
+                    and = -1; // 准备合并下一段
+                }
+            }
+            if (cnt > k) {
+                ans |= 1 << b; // 答案的这个比特位必须是 1
+                mask ^= 1 << b; // 后面不考虑这个比特位
+            }
+        }
+        return ans;
+    }
+
+
+    public static void main(String[] args) {
+        wk382 w = new wk382();
+        w.maximumLength(new int[]{5, 4, 1, 2, 2});
+    }
+}