
using Xunit;
namespace ConsoleApp {
    public class ProgramTests {
        [Fact(DisplayName = "Returns correct count for multiple occurrences")] 
        public void Returns_CorrectCount_MultipleOccurrences() {
            int[] arr = { 4, 2, 7, 4, 9, 4, 3 };
            Assert.Equal(3, Program.CountOccurrences(arr, 4));
        }

        [Fact(DisplayName = "Returns zero when value not in array")] 
        public void Returns_Zero_WhenValueNotInArray() {
            int[] arr = { 1, 2, 3, 5 };
            Assert.Equal(0, Program.CountOccurrences(arr, 4));
        }

        [Fact(DisplayName = "Returns correct count for single occurrence")] 
        public void Returns_CorrectCount_SingleOccurrence() {
            int[] arr = { 1, 2, 4, 5 };
            Assert.Equal(1, Program.CountOccurrences(arr, 4));
        }

        [Fact(DisplayName = "Works for empty array")] 
        public void Works_ForEmptyArray() {
            int[] arr = { };
            Assert.Equal(0, Program.CountOccurrences(arr, 4));
        }
    }
}

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.

Start your journey with arrays in C#: learn how to declare, initialize, and access array elements, and tackle your first real-world array challenges.

Dive deeper into arrays by learning how to search for values, filter elements, and perform calculations like finding min, max, and averages.

Advance your skills by learning how to reverse arrays, sort them manually, and understand how arrays are stored and copied in memory.

Explore two-dimensional arrays, learn to perform matrix operations, and tackle real-world challenges involving grids and tables.

Challenge: Count Occurrences

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