solved problem 461 Hamming Distance

Author: obalunenko

hamming_distance/hamming_test.go

@@ -0,0 +1,67 @@
+package hamming_distance
+
+import (
+	"fmt"
+	"testing"
+)
+
+type TestCase struct {
+	id             int
+	description    string
+	input          Input
+	expectedResult int
+}
+
+type Input struct {
+	a int
+	b int
+}
+
+type TestSuite []TestCase
+
+var ts = TestSuite{
+	TestCase{
+		id:          1,
+		description: "test case from task - different numbers",
+		input: Input{
+			a: 1,
+			b: 4,
+		},
+		expectedResult: 2,
+	},
+	TestCase{
+		id:          2,
+		description: "Diggerent length of binary",
+		input: Input{
+			a: 1,
+			b: 136,
+		},
+		expectedResult: 3,
+	},
+	TestCase{
+		id:          3,
+		description: "Same numbers",
+		input: Input{
+			a: 136,
+			b: 136,
+		},
+		expectedResult: 0,
+	},
+}
+
+func TestHamming(t *testing.T) {
+
+	for _, tc := range ts {
+		t.Run(fmt.Sprintf("Test%d", tc.id), func(t *testing.T) {
+
+			actualResult := hammingDistance(tc.input.a, tc.input.b)
+
+			if actualResult != tc.expectedResult {
+				fmt.Printf(" - Got: %d\n - Expected: %d\n", actualResult, tc.expectedResult)
+				t.Fail()
+			}
+
+		})
+	}
+
+}

hamming_distance/main.go

@@ -0,0 +1,49 @@
+package hamming_distance
+
+import (
+	"fmt"
+	"strconv"
+)
+
+func hammingDistance(x int, y int) int {
+	var result int
+	binX := strconv.FormatInt(int64(x), 2)
+	binY := strconv.FormatInt(int64(y), 2)
+
+	fmt.Printf("Before diff fix:\n - X: %s\n - Y: %s\n", binX, binY)
+	var diffLen int
+
+	switch {
+	case len(binX) < len(binY):
+		diffLen = len(binY) - len(binX)
+		binX = addLeadZeros(binX, diffLen)
+
+	case len(binX) > len(binY):
+		diffLen = len(binX) - len(binY)
+		binY = addLeadZeros(binY, diffLen)
+	}
+
+	fmt.Printf("After diff fix\n - X: %s\n - Y: %s\n", binX, binY)
+	for index, digit := range binX {
+		if string([]rune(binY)[index]) != string(digit) {
+
+			result++
+
+		}
+	}
+
+	return result
+}
+
+func addLeadZeros(bin string, diff int) string {
+	//fmt.Printf("Diff is %d\n", diff)
+	//fmt.Printf("string is %s\n", bin)
+
+	var tmp string
+	for i := 0; i < diff; i++ {
+		tmp += "0"
+		//fmt.Printf("Step[%d]: tmp is [%s]\n", i, tmp)
+	}
+	bin = tmp + bin
+	return bin
+}

hamming_distance/spec.md

@@ -0,0 +1,28 @@
+461 Hamming Distance
+https://leetcode.com/problems/hamming-distance/description/
+
+
+
+
+The Hamming distance between two integers is the number of positions 
+at which the corresponding bits are different.
+
+Given two integers x and y, calculate the Hamming distance.
+
+Note:
+`0 ≤ x, y < 231.`
+
+Example:
+```
+Input: x = 1, y = 4
+
+Output: 2
+
+Explanation:
+1   (0 0 0 1)
+4   (0 1 0 0)
+       ↑   ↑
+```
+
+
+The above arrows point to positions where the corresponding bits are different.