Merge pull request #163 from sir-gon/feature/mini_max_sum

[Hacker Rank] Warm up: Mini-Max Sum solved ✓

Author: sir-gon

algorithm-exercises-java/src/main/java/ae/hackerrank/MiniMaxSum.java

@@ -0,0 +1,39 @@
+package ae.hackerrank;
+
+import java.util.List;
+
+/**
+ * Mini-Max Sum.
+ *
+ * @link Problem definition [[docs/hackerrank/warmup/mini_max_sum.md]]
+ */
+public class MiniMaxSum {
+
+  private MiniMaxSum() {}
+
+  static java.util.logging.Logger logger = util.CustomLogger.getLogger();
+
+  /**
+   * miniMaxSum.
+   *
+   * @throws IllegalArgumentException arr Must have elements
+   */
+  public static String miniMaxSum(List<Integer> arr) throws IllegalArgumentException {
+    if (arr == null || arr.isEmpty()) {
+      throw new IllegalArgumentException("Parameter cannot be empty");
+    }
+
+    int tsum = 0;
+    int tmin = arr.get(0);
+    int tmax = arr.get(0);
+
+    for (int value : arr) {
+      tsum += value;
+
+      tmin = Math.min(tmin, value);
+      tmax = Math.max(tmax, value);
+    }
+
+    return String.format("%d %d", tsum - tmax, tsum - tmin);
+  }
+}

algorithm-exercises-java/src/test/java/ae/hackerrank/MiniMaxSumTest.java

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+package ae.hackerrank;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import java.util.Arrays;
+import java.util.List;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.TestInstance;
+import org.junit.jupiter.api.TestInstance.Lifecycle;
+
+@TestInstance(Lifecycle.PER_CLASS)
+class MiniMaxSumTest {
+
+  public class MiniMaxSumTestCase {
+    public List<Integer> input;
+    public String expected;
+
+    public MiniMaxSumTestCase(List<Integer> _input, String _expected) {
+      this.input = _input;
+      this.expected = _expected;
+    }
+  }
+
+  public List<MiniMaxSumTestCase> testCases;
+
+  @BeforeAll
+  public void setup() {
+    this.testCases = Arrays.asList(
+      new MiniMaxSumTestCase(Arrays.asList(1, 2, 3, 4, 5), "10 14"),
+      new MiniMaxSumTestCase(Arrays.asList(5, 4, 3, 2, 1), "10 14")
+    );
+  }
+
+  @Test
+  void testMiniMaxSum() {
+
+    for (MiniMaxSumTestCase testCase : this.testCases) {
+      String solutionFound = MiniMaxSum.miniMaxSum(testCase.input);
+
+      assertEquals(testCase.expected, solutionFound,
+          String.format(
+              "CompareTriplets.compareTriplets() answer must be: %s",
+              testCase.expected.toString()));
+    }
+  }
+
+  @Test
+  void testMiniMaxSumNullInput() {
+
+    IllegalArgumentException exception = assertThrows(IllegalArgumentException.class, () -> {
+      MiniMaxSum.miniMaxSum(null);
+    });
+
+    String expectedMessage = "Parameter cannot be empty";
+    String actualMessage = exception.getMessage();
+
+    assertTrue(actualMessage.contains(expectedMessage));
+  }
+
+  @Test
+  void testMiniMaxSumEmptyInput() {
+    List<Integer> input = Arrays.asList();
+
+    IllegalArgumentException exception = assertThrows(IllegalArgumentException.class, () -> {
+      MiniMaxSum.miniMaxSum(input);
+    });
+
+    String expectedMessage = "Parameter cannot be empty";
+    String actualMessage = exception.getMessage();
+
+    assertTrue(actualMessage.contains(expectedMessage));
+  }
+}

docs/hackerrank/warmup/mini_max_sum.md

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+# [Mini-Max Sum](https://www.hackerrank.com/challenges/mini-max-sum)
+
+Difficulty: #easy
+Category: #warmup
+
+Given five positive integers, find the minimum and maximum values
+that can be calculated by summing exactly four of the five integers.
+Then print the respective minimum and maximum values as a single line
+of two space-separated long integers.
+
+## Example
+
+$ arr = [1, 3, 5, 7, 9] $
+The minimum sum is $ 1 + 3 + 5 + 7 = 16 $ and the maximum sum
+is $ 3 + 5 + 7 + 9 = 24 $. The function prints
+
+```text
+16 24
+```
+
+## Function Description
+
+Complete the miniMaxSum function in the editor below.
+miniMaxSum has the following parameter(s):
+
+- arr: an array of $ 5 $ integers
+
+## Print
+
+Print two space-separated integers on one line: the minimum sum and
+the maximum sum of 4 of 5 elements.
+
+## Input Format
+
+A single line of five space-separated integers.
+
+## Constraints
+
+$ 1 \leq arra[i] \leq 10^9 $
+
+## Output Format
+
+Print two space-separated long integers denoting the respective minimum
+and maximum values that can be calculated by summing exactly four of the
+five integers. (The output can be greater than a 32 bit integer.)
+
+## Sample Input
+
+```text
+1 2 3 4 5
+```
+
+## Sample Output
+
+```text
+10 14
+```
+
+## Explanation
+
+The numbers are $ 1, 2, 3, 4, $ and $ 5 $. Calculate the following sums using
+four of the five integers:
+
+1. Sum everything except $ 1 $, the sum is $ 2 + 3 + 4 + 5 = 14 $.
+2. Sum everything except $ 2 $, the sum is $ 1 + 3 + 4 + 5 = 13 $.
+3. Sum everything except $ 3 $, the sum is $ 1 + 2 + 4 + 5 = 12 $.
+4. Sum everything except $ 4 $, the sum is $ 1 + 2 + 3 + 5 = 11 $.
+5. Sum everything except $ 5 $, the sum is $ 1 + 2 + 3 + 4 = 10 $.
+
+**Hints**: Beware of integer overflow! Use 64-bit Integer.