Summary  
Because arrays decay to pointers when passed to functions and lose their size information, you must pass the array’s length as a separate argument to enable correct and safe iteration.

General domain of usage  
Implementing functions that operate on arrays (e.g., sorting, searching, aggregating data)

#define CATCH_CONFIG_MAIN
#include <catch2/catch.hpp>

double calculateAverage(int* scores, int n);

TEST_CASE("Average for {80, 90, 75, 85, 100} should be 86", "[calculateAverage]") {
    int scores[5] = {80, 90, 75, 85, 100};
    double result = calculateAverage(scores, 5);
    REQUIRE(result == Approx(86.0)); // Summing 80 + 90 + 75 + 85 + 100, expected average: 86
}

TEST_CASE("Average for {100, 100, 100, 100} should be 100", "[calculateAverage]") {
    int scores[4] = {100, 100, 100, 100};
    double result = calculateAverage(scores, 4);
    REQUIRE(result == Approx(100.0)); // Summing 100+100+100+100, expected average: 100
}

TEST_CASE("Average for {0, 0, 0, 0} should be 0", "[calculateAverage]") {
    int scores[4] = {0, 0, 0, 0};
    double result = calculateAverage(scores, 4);
    REQUIRE(result == Approx(0.0)); // Summing 0+0+0+0, expected average: 0
}

TEST_CASE("Average for {70, 80, 75, 76} should be 75.25", "[calculateAverage]") {
    int scores[4] = {70, 80, 75, 76};
    double result = calculateAverage(scores, 4);
    REQUIRE(result == Approx(75.25)); // Summing 70+80+75+76, expected average: 75.25
}

TEST_CASE("Average for single element {50} should be 50", "[calculateAverage]") {
    int scores[1] = {50};
    double result = calculateAverage(scores, 1);
    REQUIRE(result == Approx(50.0)); // Single score 50, expected average: 50
}

test.cpp

Master the core principles of functions and their practical applications. Learn to declare, use, and optimize functions through topics like parameter handling, scope management, and overloading. Explore recursion, templates, and lambda expressions to build modular, efficient, and reusable code for real-world challenges.

Learn the core ideas of functions, their purpose, creation, and usage, along with how variable scopes influence program logic.

Challenge: Why Do We Need Array Size as an Argument?

Example

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