add leetcode: 1195,48,49

Author: CodeWater404

Algorithm/src/leetCode/multiThread/_1195AlternatePrintString.java

@@ -0,0 +1,77 @@
+package leetCode.multiThread;
+
+import java.util.function.IntConsumer;
+
+/**
+ * @author ： CodeWater
+ * @create ：2022-08-01-16:28
+ * @Function Description ：1195. 交替打印字符串
+ */
+public class _1195AlternatePrintString {
+    class FizzBuzz {
+        private int n;
+        private volatile int state = 0;
+
+        public FizzBuzz(int n) {
+            this.n = n;
+        }
+
+        // printFizz.run() outputs "fizz".
+        public void fizz(Runnable printFizz) throws InterruptedException {
+            // 注意for间隔，省力
+            for( int i = 3 ; i <= n ; i += 3 ){
+                //15的倍数不处理，交给fizzbuzz()方法处理
+                if( i % 15 == 0 ) continue;
+                while( state != 3 )
+                    Thread.yield();//让当前线程暂停
+
+                printFizz.run();
+                state = 0 ;
+
+            }
+
+        }
+
+        // printBuzz.run() outputs "buzz".
+        public void buzz(Runnable printBuzz) throws InterruptedException {
+            for( int i = 5 ; i <= n ; i += 5 ){
+                if( i % 15 == 0 ) continue;
+                while( state != 5 )
+                    Thread.yield();
+
+                printBuzz.run();
+                state = 0;
+            }
+        }
+
+        // printFizzBuzz.run() outputs "fizzbuzz".
+        public void fizzbuzz(Runnable printFizzBuzz) throws InterruptedException {
+            for( int i = 15 ; i <= n ; i += 15 ){
+                while( state != 15 )
+                    Thread.yield();
+
+                state = 0;
+                printFizzBuzz.run();
+            }
+        }
+
+        // printNumber.accept(x) outputs "x", where x is an integer.
+        public void number(IntConsumer printNumber) throws InterruptedException {
+            for( int i = 1 ; i <= n ; i++ ){
+                while( state != 0 )
+                    Thread.yield();
+                if( i % 3 != 0 && i % 5 != 0 )
+                    printNumber.accept(i);
+                else{
+                    // 能够被谁模成0就让哪个线程来处理
+                    if( i % 15 == 0 )
+                        state = 15;
+                    else if( i % 5 == 0 )
+                        state = 5;
+                    else if( i % 3 == 0 )
+                        state = 3;
+                }
+            }
+        }
+    }
+}

Algorithm/src/leetCode/subject/number1_50/_48RotatingImage.java

@@ -0,0 +1,37 @@
+package leetCode.subject.number1_50;
+
+/**
+ * @author ： CodeWater
+ * @create ：2022-08-01-19:22
+ * @Function Description ：48.旋转图像
+ */
+public class _48RotatingImage {
+    class Solution {
+        /**顺时针转90度= 先斜对角线对称反转+后对称左右反转
+         （画图很容易理解）
+         */
+        public void rotate(int[][] matrix) {
+            int n = matrix.length;
+            // 先对称反转
+            for( int i = 0 ; i < n ; i++ ){
+                // 只枚举下三角部分
+                for(int j = 0 ; j < i ; j++ ){
+                    swap( matrix , i , j , j , i );
+                }
+            }
+
+            // 在对称反转
+            for( int i = 0 ; i < n ; i++ ){
+                for( int j = 0 , k = n - 1 ; j < k ; j++ , k-- )
+                    swap(matrix , i , j , i , k );
+            }
+        }
+
+        public void swap( int[][] matrix , int x1 , int y1 , int x2 , int y2 ){
+            int temp = matrix[x1][y1] ;
+            matrix[x1][y1] = matrix[x2][y2];
+            matrix[x2][y2] = temp;
+
+        }
+    }
+}

Algorithm/src/leetCode/subject/number1_50/_49Alphabet.java

@@ -0,0 +1,32 @@
+package leetCode.subject.number1_50;
+
+import java.util.*;
+
+/**
+ * @author ： CodeWater
+ * @create ：2022-08-01-18:55
+ * @Function Description ：49.字母异位词分组
+ */
+public class _49Alphabet {
+    class Solution {
+        public List<List<String>> groupAnagrams(String[] strs) {
+            Map<String , List<String> > hash = new HashMap<>();
+            for( int i = 0 ; i < strs.length ; i++ ){
+                char[] c = strs[i].toCharArray();
+                // 把字符变成字符串排序之后就好处理了，原来乱序的都会一样
+                Arrays.sort( c );
+                String s = new String(c);
+                // 一开始如果不在hash中，新建一个对应的list
+                if( !hash.containsKey(s) )
+                    hash.put( s , new ArrayList<String>() );
+                // s有对应的键，就把他加入到对应的值的list数组中去
+                hash.get(s).add(strs[i]);
+            }
+
+            List<List<String>> res = new ArrayList<>();
+            for(List<String> temp : hash.values() ) res.add(temp);
+
+            return res;
+        }
+    }
+}