An alternative method for js pure numbers not to be arranged repeatedly

After referring to the carefree cosin method (thanks), the solution is as follows:
Copy codeThe Code is as follows:
// A random number, used for Simulation
Var baseNum = [];
For (var I = 0; I <100000; I ++ ){
Random = Math. floor (Math. random () * I );
BaseNum. push (random );
}
Var baseNumLen = baseNum. length;
Var numSubscript = [];
// Place numbers as subscripts and values in another array for sorting and non-repetition
For (var I = 0; I <basenumlen; I ++ ){
If (numSubscript [baseNum [I] = undefined) numSubscript [baseNum [I] = baseNum [I];
}
// Remove the null value and reverse it.
BaseNum = numSubscript. join (','). replace (/([,] +)/ig, ','). split (','). reverse ();
Document. write (baseNum );

Question:
If the array is self-generated, the code written in the result of the customer service is very good. (AWESOME)
Copy codeThe Code is as follows:
Var baseNum = [], tmp = {}, v;
For (var I = 0; I <100000; I ++ ){
Tmp [Math. floor (Math. random () * I)] = true;
};
I = 0;
For (var k in tmp ){
BaseNum [I ++] = k;
};
BaseNum. sort (fn );
Function fn (x, y ){
Return x-y> 0? 1:-1
}
Document. write (baseNum. join (''));