Write a function that takes two Point structs and returns the distance between them. Use the distance formula: square root of the sum of squared differences. Include <cmath> for sqrt.
Define struct Point { int x; int y; };. Write double distance(Point p1, Point p2) that calculates the distance. Access members with dots: p1.x, p1.y, p2.x, p2.y. Test with Point a{0, 0}; Point b{3, 4};.
Distance should be 5. This practices struct parameters, member access, and returning values.