feat: kata/elevator-distance

Author: ParanoidUser

kata/7-kyu/elevator-distance/README.md

@@ -1,8 +1,10 @@
 # [Elevator Distance](https://www.codewars.com/kata/elevator-distance "https://www.codewars.com/kata/59f061773e532d0c87000d16")
 
-Imagine you start on the 5th floor of a building, then travel down to the 2nd floor, then back up to the 8th floor. You have travelled a total of 3 + 6 = 9 floors of distance.
+Imagine you start on the 5th floor of a building, then travel down to the 2nd floor, then back up to the 8th floor. You have travelled a
+total of 3 + 6 = 9 floors of distance.
 
-Given an array representing a series of floors you must reach by elevator, return an integer representing the total distance travelled for visiting each floor in the array in order. 
+Given an array representing a series of floors you must reach by elevator, return an integer representing the total distance travelled for
+visiting each floor in the array in order.
 
 ```
 // simple examples
@@ -15,4 +17,4 @@ Given an array representing a series of floors you must reach by elevator, retur
 [3,3] => 0
 ```
 
-Array will always contain at least 2 floors. Random tests will contain 2-20 elements in array, and floor values between 0 and 30.
+Array will always contain at least 2 floors. Random tests will contain 2-20 elements in array, and floor values between 0 and 30.

kata/7-kyu/elevator-distance/main/Kata.java

@@ -0,0 +1,7 @@
+import static java.util.stream.IntStream.range;
+
+interface Kata {
+  static int elevatorDistance(int[] arr) {
+    return range(0, arr.length - 1).reduce(0, (s, i) -> s + Math.abs(arr[i] - arr[i + 1]));
+  }
+}

kata/7-kyu/elevator-distance/test/ElevatorDistanceTest.java

@@ -0,0 +1,23 @@
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.params.provider.Arguments.arguments;
+
+import java.util.stream.Stream;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.Arguments;
+import org.junit.jupiter.params.provider.MethodSource;
+
+class ElevatorDistanceTest {
+  private static Stream<Arguments> testData() {
+    return Stream.of(
+        arguments(new int[]{5, 2, 8}, 9),
+        arguments(new int[]{1, 2, 3}, 2),
+        arguments(new int[]{7, 1, 7, 1}, 18)
+    );
+  }
+
+  @ParameterizedTest
+  @MethodSource("testData")
+  void sample(int[] arr, int expected) {
+    assertEquals(expected, Kata.elevatorDistance(arr));
+  }
+}