What is the mean of below statement?

class age
{
private:
int day;
int month;
int year;
public:
age():day(1), month(1), year(1)
{}
void method(age a1, age a2)
{
//////
}
};

What is mean of age():day(1), month(1), year(1)
{} statements???

The age() is a constructor for the class. Here the constructor is initializing the data members day, month and year to 1.

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