feat: kata/evens-times-last (#793)

* docs: kata description

* feat: kata/evens-times-last

---------

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

Author: github-actions[bot]

kata/7-kyu/evens-times-last/README.md

@@ -0,0 +1,8 @@
+# [Evens times last](https://www.codewars.com/kata/evens-times-last "https://www.codewars.com/kata/5a1a9e5032b8b98477000004")
+
+Given a sequence of integers, return the sum of all the integers that have an even index, multiplied by the integer at
+the last index.
+
+Indices in sequence start from 0.
+
+If the sequence is empty, you should return 0.

kata/7-kyu/evens-times-last/main/Kata.java

@@ -0,0 +1,7 @@
+import static java.util.stream.IntStream.range;
+
+interface Kata {
+  static int evenLast(int[] nums) {
+    return range(0, nums.length).reduce(0, (s, i) -> i % 2 == 0 ? s + nums[i] * nums[nums.length - 1] : s);
+  }
+}

kata/7-kyu/evens-times-last/test/EvenLastTest.java

@@ -0,0 +1,25 @@
+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 EvenLastTest {
+  private static Stream<Arguments> testData() {
+    return Stream.of(
+        arguments(new int[0], 0),
+        arguments(new int[]{2, 2, 2, 2}, 8),
+        arguments(new int[]{2, 3, 4, 5}, 30),
+        arguments(new int[]{1, 3, 3, 1, 10}, 140),
+        arguments(new int[]{-11, 3, 3, 1, 10}, 20)
+    );
+  }
+
+  @ParameterizedTest
+  @MethodSource("testData")
+  void sample(int[] arr, int expected) {
+    assertEquals(expected, Kata.evenLast(arr));
+  }
+}

kata/7-kyu/index.md

@@ -163,6 +163,7 @@
 - [E.S.P.  Cards](esp-cards "596ef174e4cab6813600004d")
 - [Even numbers in an array](even-numbers-in-an-array "5a431c0de1ce0ec33a00000c")
 - [Even or Odd - Which is Greater?](even-or-odd-which-is-greater "57f7b8271e3d9283300000b4")
+- [Evens times last](evens-times-last "5a1a9e5032b8b98477000004")
 - [Excel sheet column numbers](excel-sheet-column-numbers "55ee3ebff71e82a30000006a")
 - [Excessively Abundant Numbers](excessively-abundant-numbers "56a75b91688b49ad94000015")
 - [Exclamation marks series #5: Remove all exclamation marks from the end of words](exclamation-marks-series-number-5-remove-all-exclamation-marks-from-the-end-of-words "57faf32df815ebd49e000117")