#include using namespace std; int sum(int x = 20, int y = 30) { int result = x + y; return result; // Create a function sum() } int volume(int l=3, int w=4, int h=5) { return l * w * h / 2; // Create a function volume() // for triangles volume } int main() { int n = 40; int m = 60; // declare n = 40 and m = 60 int total_NM = n + m; // declare total_NM = n + m // Function sum() int total = sum(n, m); cout << "total = " << total << endl; // total = sum(n + m) int total2 = sum(n); cout << "total2 = " << total2 << endl; // total2 = sum(n + y) int total3 = sum(); cout << "total3 = " << total3 << endl; // total3 = sum(x + y) int total4 = sum() + total_NM; cout << "total4 = " << total4 << endl; // total4 = sum(x + y) + total_NM int total5 = total * 2 - total2 - total3 + total4; cout << "total5 = " << total5 << endl; /* total5 = sum(n + m) * 2 - sum(n + y) - sum(x + y) + (sum(x + y) + total_NM) */ cout << endl; // Function volume() int triangle_Volume = volume(2,2,2); cout << "Triangle Volume = "; cout << triangle_Volume << endl; // 2 * 2 * 2 / 2 int triangle_Volume2 = volume(2,2); cout << "Triangle Volume2 = "; cout << triangle_Volume2 << endl; // 2 * 2 * 5 / 2 int triangle_Volume3 = volume(2); cout << "Triangle Volume3 = "; cout << triangle_Volume3 << endl; // 2 * 4 * 5 / 2 int triangle_Volume4 = volume(); cout << "Triangle Volume4 = "; cout << triangle_Volume4 << endl; // 3 * 4 * 5 / 2 }

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