feat: Improvement of ArrayMode by adding ArrayModeInPlace implementat…

…ion (#211)

* Create ArrayModeInPlaceSnippet.java and ArrayModeInPlaceSnippetTest.java

* Fix ArrayModeInPlaceSnippetTest

* Fix the ArrayModeInPlaceSnippetTest line length issue

* update README

README.md

@@ -401,6 +401,38 @@ public static int modeArray(int[] arr) {
         }
 ```
 
+### Find mode of integer array (2)
+
+```java
+  public static int modeArrayInPlace(int[] arr) {
+    if (arr.length == 0) {
+    return 0;
+    }
+
+    Arrays.sort(arr);
+
+    int mode = arr[0];
+    int maxcount = 1;
+    int count = 1;
+
+    for (int i = 1; i < arr.length; i++) {
+    if (arr[i] == arr[i - 1]) {
+    count++;
+    } else {
+    if (count > maxcount) {
+    maxcount = count;
+    mode = arr[i - 1];
+    }
+    count = 1;
+    }
+    }
+    if (count > maxcount) {
+    mode = arr[arr.length - 1];
+    }
+    return mode;
+    }
+```
+
 ### Find sum of integer array
 
 ```java

src/main/java/array/ArrayModeInPlaceSnippet.java

@@ -0,0 +1,67 @@
+/*
+ * MIT License
+ *
+ * Copyright (c) 2017-2022 Ilkka Seppälä
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package array;
+
+import java.util.Arrays;
+
+/**
+ * ArrayModeSnippet.
+ */
+public class ArrayModeInPlaceSnippet {
+
+  /**
+  * Returns the mode of the array.
+  *
+  * @param arr array to find mode in it
+  * @return mode of array
+  */
+  public static int modeArrayInPlace(int[] arr) {
+    if (arr.length == 0) {
+      return 0;
+    }
+
+    Arrays.sort(arr);
+
+    int mode = arr[0];
+    int maxcount = 1;
+    int count = 1;
+
+    for (int i = 1; i < arr.length; i++) {
+      if (arr[i] == arr[i - 1]) {
+        count++;
+      } else {
+        if (count > maxcount) {
+          maxcount = count;
+          mode = arr[i - 1];
+        }
+        count = 1;
+      }
+    }
+    if (count > maxcount) {
+      mode = arr[arr.length - 1];
+    }
+    return mode;
+  }
+}

src/test/java/array/ArrayModeInPlaceSnippetTest.java

@@ -0,0 +1,45 @@
+/*
+ * MIT License
+ *
+ * Copyright (c) 2017-2022 Ilkka Seppälä
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package array;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import org.junit.jupiter.api.Test;
+
+/**
+ * Tests for 30 Seconds of Java code library.
+ */
+public class ArrayModeInPlaceSnippetTest {
+  /**
+  * Test for {@link ArrayModeInPlaceSnippet #ArrayModeInPlaceSnippet(int[])}.
+  */
+  @Test
+    void testModeArray() {
+    assertEquals(2, ArrayModeInPlaceSnippet.modeArrayInPlace(new int[]{1, 2, 3, 2, 4, 2, 2}));
+    assertEquals(-8, ArrayModeInPlaceSnippet.modeArrayInPlace(new int[]{-43, -8, -8, -10, -8, -6}));
+    assertEquals(0, ArrayModeInPlaceSnippet.modeArrayInPlace(new int[]{-4, 0, -2, -1, 0}));
+    assertEquals(1, ArrayModeInPlaceSnippet.modeArrayInPlace(new int[]{1, 1, 1, 1, 1, 1}));
+  }
+}