Do you really know JavaScript?

Specify their values

1. typeof (NAN), typeof (infinity), typeof (null), typeof (undefined)
2. Nan = Nan
3. Nan! = Nan
4. Nan> = Nan
5. null = undefined
6. null> = undefined
7. null <= undefined
8. parseint ("123abc ")
9. "123abc"-0
10. Infinity> 10
11. Infinity> "ABC"
12. Infinity = Nan
13. True = 1
14. New String ("ABC") = "ABC"
15. New String ("ABC") = "ABC"

Output results

1,
VaR A = "123abc ";
Alert (typeof (A ++ ));
Alert ();

2,
VaR A = "123abc ";
A. valueof = function () {return parseint ();}
Alert (++ );
Alert (a-0 );

3,
VaR A = new object ();
A. tostring = function () {return "123abc ";}
A. valueof = function () {return parseint ();}
Alert (++ );
Alert (a-0 );

4,
String. Prototype. valueof = function ()
{
Return parsefloat (this );
}
Alert ("123abc"> 122 );
Alert (new string ("Fig")> 122 );

5,
VaR S = new string ("ABC ");
Alert (typeof (S) = typeof ("ABC "));
Alert (S = "ABC ");
Alert (S. tostring () = s );

6,
VaR A = new object ();
A. tostring = function () {return ""};
VaR B = new object ();
B. tostring = function () {return "B "};
Alert (A> B );
A. valueof = function () {return 1 };
B. valueof = function () {return 0 };
Alert (A> B );

7,
Function step ()
{
Return function (X)
{
Return x + A ++;
}
}
VaR A = step (10 );
VaR B = step (20 );
Alert (A (10 ));
Alert (B (10 ));