Merge pull request #150 from fartem/find-the-pivot-integer

2023-01-06 update: added "2485. Find the Pivot Integer"

Author: fartem

README.md

@@ -424,6 +424,7 @@ Profile on LeetCode: [fartem](https://leetcode.com/fartem/).
 | 2455. Average Value of Even Numbers That Are Divisible by Three          | [Link](https://leetcode.com/problems/average-value-of-even-numbers-that-are-divisible-by-three/)          | [Link](./src/main/java/com/smlnskgmail/jaman/leetcodejava/easy/AverageValueOfEvenNumbersThatAreDivisibleByThree.java)             |
 | 2469. Convert the Temperature                                            | [Link](https://leetcode.com/problems/convert-the-temperature/)                                            | [Link](./src/main/java/com/smlnskgmail/jaman/leetcodejava/easy/ConvertTheTemperature.java)                                        |
 | 2481. Minimum Cuts to Divide a Circle                                    | [Link](https://leetcode.com/problems/minimum-cuts-to-divide-a-circle/)                                    | [Link](./src/main/java/com/smlnskgmail/jaman/leetcodejava/easy/MinimumCutsToDivideACircle.java)                                   |
+| 2485. Find the Pivot Integer                                             | [Link](https://leetcode.com/problems/find-the-pivot-integer/)                                             | [Link](./src/main/java/com/smlnskgmail/jaman/leetcodejava/easy/FindThePivotInteger.java)                                          |
 | 2490. Circular Sentence                                                  | [Link](https://leetcode.com/problems/circular-sentence/)                                                  | [Link](./src/main/java/com/smlnskgmail/jaman/leetcodejava/easy/CircularSentence.java)                                             |
 | 2496. Maximum Value of a String in an Array                              | [Link](https://leetcode.com/problems/maximum-value-of-a-string-in-an-array/)                              | [Link](./src/main/java/com/smlnskgmail/jaman/leetcodejava/easy/MaximumValueOfAStringInAnArray.java)                               |
 | 2500. Delete Greatest Value in Each Row                                  | [Link](https://leetcode.com/problems/delete-greatest-value-in-each-row/)                                  | [Link](./src/main/java/com/smlnskgmail/jaman/leetcodejava/easy/DeleteGreatestValueInEachRow.java)                                 |

src/main/java/com/smlnskgmail/jaman/leetcodejava/easy/FindThePivotInteger.java

@@ -0,0 +1,25 @@
+package com.smlnskgmail.jaman.leetcodejava.easy;
+
+// https://leetcode.com/problems/find-the-pivot-integer/
+public class FindThePivotInteger {
+
+    private final int input;
+
+    public FindThePivotInteger(int input) {
+        this.input = input;
+    }
+
+    public int solution() {
+        int sum = input * (input + 1) / 2;
+        int value = 0;
+        for (int i = input; i > 0; i--) {
+            value += i;
+            if (sum == value) {
+                return i;
+            }
+            sum -= i;
+        }
+        return -1;
+    }
+
+}

src/test/java/com/smlnskgmail/jaman/leetcodejava/easy/FindThePivotIntegerTest.java

@@ -0,0 +1,16 @@
+package com.smlnskgmail.jaman.leetcodejava.easy;
+
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+
+public class FindThePivotIntegerTest {
+
+    @Test
+    public void defaultTests() {
+        assertEquals(6, new FindThePivotInteger(8).solution());
+        assertEquals(1, new FindThePivotInteger(1).solution());
+        assertEquals(-1, new FindThePivotInteger(4).solution());
+    }
+
+}