26. Remove Duplicates from Sorted Array

Author: maxvoronov

README.md

@@ -1,6 +1,6 @@
 # LeetCode
 
-![Problems Solved](https://img.shields.io/badge/Problems%20Solved-26%20%2F%203008-1f425f?logo=leetcode)
+![Problems Solved](https://img.shields.io/badge/Problems%20Solved-27%20%2F%203008-1f425f?logo=leetcode)
 ![Language: Golang](https://img.shields.io/badge/language-Golang-00ADD8?logo=go)
 ![Language: Rust](https://img.shields.io/badge/language-Rust-00ADD8?logo=rust)
 ![Language: Bash](https://img.shields.io/badge/language-Bash-00ADD8?logo=gnubash&logoColor=f5f5f5)
@@ -17,6 +17,7 @@
 |  13 | [Roman to Integer](https://leetcode.com/problems/roman-to-integer/)                                                             | [Go](go/0013_roman_to_integer)                                                  |     🟢     |      Hash Table, Math, String      |
 |  17 | [Letter Combinations of a Phone Number](https://leetcode.com/problems/letter-combinations-of-a-phone-number/)                   | [Go](go/0017_letter_combinations_phone)                                         |     🟡     |  Hash Table, String, Backtracking  |
 |  20 | [Valid Parentheses](https://leetcode.com/problems/valid-parentheses/)                                                           | [Go](go/0020_valid_parentheses)                                                 |     🟢     |           String, Stack            |
+|  26 | [Remove Duplicates from Sorted Array](https://leetcode.com/problems/remove-duplicates-from-sorted-array/)                       | [Go](go/0026_remove_duplicates_from_array)                                      |     🟢     |           Array, Pointer           |
 |  35 | [Search Insert Position](https://leetcode.com/problems/search-insert-position/)                                                 | [Go](go/0035_search_insert_position), [Rust](rust/_0035_search_insert_position) |     🟢     |        Array, Binary Search        |
 |  50 | [Pow(x, n)](https://leetcode.com/problems/powx-n/)                                                                              | [Go](go/0050_powx_n)                                                            |     🟡     |          Math, Recursion           |
 |  69 | [Sqrt(x)](https://leetcode.com/problems/sqrtx/)                                                                                 | [Go](go/0069_sqrtx), [Rust](rust/_0069_sqrtx)                                   |     🟢     |        Math, Binary Search         |

go/0026_remove_duplicates_from_array/solution.go

@@ -0,0 +1,22 @@
+package remove_duplicates_from_array
+
+func removeDuplicates(nums []int) int {
+	if len(nums) <= 1 {
+		return len(nums)
+	}
+
+	lastNum := nums[0] // Last number for comparing
+	rCur, wCur := 1, 1 // Read and write cursors
+
+	for rCur < len(nums) {
+		if nums[rCur] > lastNum {
+			lastNum = nums[rCur]
+			nums[wCur] = lastNum
+			wCur++
+		}
+
+		rCur++
+	}
+
+	return wCur
+}

go/0026_remove_duplicates_from_array/solution_test.go

@@ -0,0 +1,32 @@
+package remove_duplicates_from_array
+
+import (
+	"reflect"
+	"testing"
+)
+
+func Test_containsDuplicate(t *testing.T) {
+	tests := []struct {
+		input   []int
+		want    int
+		wantArr []int
+	}{
+		{input: []int{0, 0, 0, 1, 1, 1, 2, 2, 3, 3, 4}, want: 5, wantArr: []int{0, 1, 2, 3, 4, 0, 0, 0, 0, 0}},
+		{input: []int{1, 1, 2}, want: 2, wantArr: []int{1, 2, 0}},
+		{input: []int{1, 2}, want: 2, wantArr: []int{1, 2}},
+		{input: []int{1}, want: 1, wantArr: []int{1}},
+		{input: []int{}, want: 0, wantArr: []int{}},
+	}
+
+	for i, tc := range tests {
+		got := removeDuplicates(tc.input)
+
+		if tc.want != got {
+			t.Fatalf("Case #%d: expected: %v, got: %v", i+1, tc.want, got)
+		}
+
+		if !reflect.DeepEqual(tc.wantArr[:got], tc.input[:got]) {
+			t.Fatalf("Case #%d: invalid modified slice - expected: %v, got: %v", i+1, tc.wantArr[:got], tc.input[:got])
+		}
+	}
+}