如何使用其参数化构造函数初始化成员

It's hard to describe without code so here goes: I'm trying to prototype an object (b) in the header file of another(a), then in the constructor of (a) call (b)'s constructor and pass it values, so i can then use the methods of b which depend on its constructor and the values passed to it, but the way im doing gives: red underlined in the open bracket of pricing's constructor says: "no default constructor exists for monteCarlo" and then on the next line m is underlined red saying: "call of object of a class type without appropriate operator() or conversion functionsto pointer-to-function type". Any other critic of my program is very welcome, i am trying to learn to program, and well.It's hard to describe without code so here goes