feat: kata/elevator-distance (#792)

* docs: kata description

* feat: kata/elevator-distance

---------

Co-authored-by: ParanoidUser <5120290+ParanoidUser@users.noreply.github.com>

Author: github-actions[bot]

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

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+# [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.
+
+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
+[5,2,8] => 9
+[1,2,3] => 2
+[7,1,7,1] => 18
+
+// if two consecutive floors are the same,
+//distance travelled between them is 0
+[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.

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

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+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

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+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));
+  }
+}

kata/7-kyu/index.md

@@ -157,6 +157,7 @@
 - [EAN Validation](ean-validation "55563df50dda59adf900004d")
 - [Easy Line](easy-line "56e7d40129035aed6c000632")
 - [Easy wallpaper](easy-wallpaper "567501aec64b81e252000003")
+- [Elevator Distance](elevator-distance "59f061773e532d0c87000d16")
 - [Eliminate the intruders! Bit manipulation](eliminate-the-intruders-bit-manipulation "5a0d38c9697598b67a000041")
 - [Email Address Obfuscator](email-address-obfuscator "562d8d4c434582007300004e")
 - [E.S.P.  Cards](esp-cards "596ef174e4cab6813600004d")