In C++

A Pyramid with a square base, 4 triangular faces, and an apex is a square pyramid. Write a function surfaceArea to calculate and return the surface area of a square pyramid. The function takes two double parameters - the base length(b) and slant height(h) of a square pyramid, and calculates and returns the surface area as a double. Function specifications: The function name: surfaceArea The function parameters in this order) o The base length, double o The slant height, double The function return value: surface area, double The function should not print anything. Edge cases: if one or more arguments are not positive numbers, then it should return -1 Sample run 1 (bold is user input) Enter the base length: 3 Enter the slant height: 4 The surface area: 33 Sample run 2 (bold is user input) Enter the base length: 3 Enter the slant height: -1 Invalid values