Question #49: What is the output of the program?

Question #49: What is the output of the program?
55% on 10074 times asked

#include <iostream>
            class Foo
            {
            public:
            char c;
            static double sd;
            double d;
            int i;
            };
            int main(int argc, char** argv)
            {
            Foo f = { 72, 3.14 };
            std::cout << f.c + f.d + f.i << std::endl;
            return 0;
            }
72
75.14 - correct
ill-formed
undefined

description: "An aggregate is an array or a class with no user-declared constructors, no private or protected non-static data members, no base classes, and no virtual functions." Aggregates can be initialized by "brace-enclosed, comma separated list of initializer-clauses for the members of the aggregate, written in increasing subscript or member order." Static data members are skipped during this type of initialization so 3.14 initializes d and not sd in this example "If there are fewer initializers in the list than there are members in the aggregate, then each member not explicitly initialized shall be value-initialized". So in this example i is value-initialized to 0.

原文地址:https://www.cnblogs.com/rickiedu/p/1455054.html