Algorithms: Sort Colors

Author: maxvoronov

README.md

@@ -1,6 +1,6 @@
 # LeetCode
 
-![Problems Solved](https://img.shields.io/badge/Problems%20Solved-16%20%2F%202046-1f425f?logo=leetcode) 
+![Problems Solved](https://img.shields.io/badge/Problems%20Solved-17%20%2F%202046-1f425f?logo=leetcode) 
 ![Language: Golang](https://img.shields.io/badge/language-Golang-00ADD8?logo=go) 
 
 ### LeetCode Algorithm
@@ -16,6 +16,7 @@
 | 20  | [Valid Parentheses](https://leetcode.com/problems/valid-parentheses/) | [Go](go/0020_valid_parentheses) | 🟢 |
 | 35  | [Search Insert Position](https://leetcode.com/problems/search-insert-position/) | [Go](go/0035_search_insert_position) | 🟢 |
 | 50  | [Pow(x, n)](https://leetcode.com/problems/powx-n/) | [Go](go/0050_powx_n) | 🟡 |
+| 75  | [Sort Colors](https://leetcode.com/problems/sort-colors/) | [Go](go/0075_sort_colors) | 🟡 |
 | 155 | [Min Stack](https://leetcode.com/problems/min-stack/) | [Go](go/0155_min_stack) | 🟢 |
 | 226 | [Invert Binary Tree](https://leetcode.com/problems/invert-binary-tree/) | [Go](go/0226_invert_binary_tree) | 🟢 |
 | 283 | [Move Zeroes](https://leetcode.com/problems/move-zeroes/) | [Go](go/0283_move_zeroes) | 🟢 |

go/0075_sort_colors/solution.go

@@ -0,0 +1,21 @@
+package sort_colors
+
+func sortColors(nums []int) {
+	numLen := len(nums)
+	if numLen <= 1 {
+		return
+	}
+
+	// Swap elements in-place loop
+	lShift, rShift := 0, 0
+	for i := 0; i < numLen-rShift; i++ {
+		if nums[i] == 0 {
+			nums[i], nums[lShift] = nums[lShift], nums[i]
+			lShift++
+		} else if nums[i] == 2 {
+			nums[i], nums[numLen-rShift-1] = nums[numLen-rShift-1], nums[i]
+			rShift++
+			i--
+		}
+	}
+}

go/0075_sort_colors/solution_test.go

@@ -0,0 +1,32 @@
+package sort_colors
+
+import (
+	"reflect"
+	"testing"
+)
+
+func Test_sortColors(t *testing.T) {
+	tests := []struct {
+		input []int
+		want  []int
+	}{
+		{input: []int{2, 0, 2, 1, 1, 0}, want: []int{0, 0, 1, 1, 2, 2}},
+		{input: []int{2, 0, 2, 1, 1, 1}, want: []int{0, 1, 1, 1, 2, 2}},
+		{input: []int{2, 2, 2, 1, 1, 1}, want: []int{1, 1, 1, 2, 2, 2}},
+		{input: []int{1, 2, 2, 0, 1}, want: []int{0, 1, 1, 2, 2}},
+		{input: []int{0, 1, 2, 2}, want: []int{0, 1, 2, 2}},
+		{input: []int{1, 2, 0}, want: []int{0, 1, 2}},
+		{input: []int{2, 0, 1}, want: []int{0, 1, 2}},
+		{input: []int{2, 2, 2}, want: []int{2, 2, 2}},
+		{input: []int{1}, want: []int{1}},
+		{input: []int{0}, want: []int{0}},
+		{input: []int{}, want: []int{}},
+	}
+
+	for i, tc := range tests {
+		sortColors(tc.input)
+		if !reflect.DeepEqual(tc.want, tc.input) {
+			t.Fatalf("Case #%d: expected: %v, got: %v", i+1, tc.want, tc.input)
+		}
+	}
+}