+ struct key_val {
+ int nKey;
+ int nVal;
+
+ key_val()
+ {}
+
+ key_val( int key )
+ : nKey( key )
+ , nVal( key )
+ {}
+
+ key_val( int key, int val )
+ : nKey( key )
+ , nVal( val )
+ {}
+
+ key_val( key_val const& v )
+ : nKey( v.nKey )
+ , nVal( v.nVal )
+ {}
+
+ int key() const
+ {
+ return nKey;
+ }
+ };
+
+ struct int_item2: public key_val, public stat
+ {
+ int_item2()
+ {}
+
+ explicit int_item2( int key )
+ : key_val( key )
+ {}
+
+ int_item2( int key, int val )
+ : key_val( key, val )
+ {}
+
+ int_item2( int_item2 const& v )
+ : key_val( v )
+ , stat()
+ {}
+ };
+