Resolve "Number of Steps to Reduce a Number in Binary Representation to

One" problem

Author: dkoval

src/main/java/com/github/dkoval/leetcode/challenge/NumberOfStepsToReduceNumberInBinaryRepresentationToOne.java

@@ -45,4 +45,32 @@ public int numSteps(String s) {
             return steps + carry;
         }
     }
+
+    class NumberOfStepsToReduceNumberInBinaryRepresentationToOneRev2 implements NumberOfStepsToReduceNumberInBinaryRepresentationToOne {
+
+        @Override
+        public int numSteps(String s) {
+            final var n = s.length();
+
+            var count = 0;
+            var carry = 0;
+            for (var i = n - 1; i > 0; i--) {
+                var digit = s.charAt(i) - '0';
+                digit += carry;
+                carry = digit / 2;
+                digit %= 2;
+                if (digit == 1) {
+                    carry++;
+                    count++;
+                }
+                count++;
+            }
+
+            if (carry > 0) {
+                count++;
+            }
+
+            return count;
+        }
+    }
 }

src/test/kotlin/com/github/dkoval/leetcode/challenge/NumberOfStepsToReduceNumberInBinaryRepresentationToOneTest.kt

@@ -1,6 +1,7 @@
 package com.github.dkoval.leetcode.challenge
 
 import com.github.dkoval.leetcode.challenge.NumberOfStepsToReduceNumberInBinaryRepresentationToOne.NumberOfStepsToReduceNumberInBinaryRepresentationToOneRev1
+import com.github.dkoval.leetcode.challenge.NumberOfStepsToReduceNumberInBinaryRepresentationToOne.NumberOfStepsToReduceNumberInBinaryRepresentationToOneRev2
 import org.junit.jupiter.api.Assertions.assertEquals
 import org.junit.jupiter.api.Nested
 import org.junit.jupiter.api.extension.ExtensionContext
@@ -32,6 +33,16 @@ internal class NumberOfStepsToReduceNumberInBinaryRepresentationToOneTest {
             NumberOfStepsToReduceNumberInBinaryRepresentationToOneRev1().test(s, expected)
         }
     }
+
+    @Nested
+    inner class NumberOfStepsToReduceNumberInBinaryRepresentationToOneRev2Test {
+
+        @ParameterizedTest
+        @ArgumentsSource(InputArgumentsProvider::class)
+        fun `should return the number of steps to reduce it to 1`(s: String, expected: Int) {
+            NumberOfStepsToReduceNumberInBinaryRepresentationToOneRev2().test(s, expected)
+        }
+    }
 }
 
 private fun NumberOfStepsToReduceNumberInBinaryRepresentationToOne.test(s: String, expected: Int) {