Does compiler create default constructor when we write our own?

　　

　　In C++, compiler by default creates default constructor for every class. But, if we define our own constructor, compiler doesn’t create the default constructor.

　　For example, program 1 compiles without any error, but compilation of program 2 fails with error “no matching function for call to `myInteger::myInteger()’ ”

　　Program 1

 1 #include<iostream>
 2
 3 using namespace std;
 4
 5 class myInteger
 6 {
 7    private:
 8      int value;
 9
10      //...other things in class
11 };
12
13 int main()
14 {
15   myInteger I1;
16   getchar();
17   return 0;
18 }

　　Program 2

 1 #include<iostream>
 2
 3 using namespace std;
 4
 5 class myInteger
 6 {
 7    private:
 8      int value;
 9    public:
10      myInteger(int v)  // parametrized constructor
11      {  value = v;  }
12
13      //...other things in class
14 };
15
16 int main()
17 {
18   myInteger I1;
19   getchar();
20   return 0;
21 }

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　　2013-11-26　　10:11:05