请教

头文件为

#include
class data
{
private:
 int x;
public:
 void init(int a)
 {
  x=a;
 }
 void invshow()
 {
  for( ; x ; )
  {
  cout<  x=x/10;
  }
  cout< }
};
源文件为

#include "3-6.h"
int main()
{
 int a;
 cin>>a;
 data A(a);
 A.invshow();
 return 0;
}

功能是想输入一个正整数，逆序输出。调试时错误为： error C2664: '__thiscall data::data(const class data &)' : cannot convert parameter 1 from 'int' to 'const class data &'
        Reason: cannot convert from 'int' to 'const class data'
        No constructor could take the source type, or constructor overload resolution was ambiguous
Error executing cl.exe.

我不明白  data A(a);
 A.invshow();
 return 0;

麻烦各位大侠指导！