
using Xunit;
namespace ConsoleApp {
    public class ProgramTests {
        [Fact(DisplayName = "RemoveDuplicates returns one occurrence of each value")] 
        public void RemoveDuplicates_ReturnsUniqueValues() {
            int[] input = {1, 2, 2, 3, 3, 3, 4};
            int[] expected = {1, 2, 3, 4};
            int[] result = Program.RemoveDuplicates(input);
            Assert.Equal(expected, result);
        }

        [Fact(DisplayName = "RemoveDuplicates preserves order of first appearance")] 
        public void RemoveDuplicates_PreservesOrder() {
            int[] input = {5, 7, 5, 3, 7, 2};
            int[] expected = {5, 7, 3, 2};
            int[] result = Program.RemoveDuplicates(input);
            Assert.Equal(expected, result);
        }

        [Fact(DisplayName = "RemoveDuplicates returns all elements if no duplicates")] 
        public void RemoveDuplicates_NoDuplicates() {
            int[] input = {10, 20, 30};
            int[] expected = {10, 20, 30};
            int[] result = Program.RemoveDuplicates(input);
            Assert.Equal(expected, result);
        }

        [Fact(DisplayName = "RemoveDuplicates returns single value when all elements are duplicates")] 
        public void RemoveDuplicates_AllDuplicates() {
            int[] input = {8, 8, 8, 8};
            int[] expected = {8};
            int[] result = Program.RemoveDuplicates(input);
            Assert.Equal(expected, result);
        }

        [Fact(DisplayName = "RemoveDuplicates returns empty array for empty input")] 
        public void RemoveDuplicates_EmptyArray() {
            int[] input = {};
            int[] expected = {};
            int[] result = Program.RemoveDuplicates(input);
            Assert.Equal(expected, result);
        }
    }
}

ProgramTests.cs

Master the essentials and advanced techniques of working with arrays in C#. This course guides you from the basics of declaring and initializing arrays, through practical manipulation, searching, and advanced operations like sorting and matrix calculations. Each section blends engaging theory with real-world themed challenges to ensure a hands-on, beginner-friendly learning experience.

Challenge: Remove Duplicates

Solution