Random JS BF generator

https://codegolf.stackexchange.com/questions/36645/brainfuckedbotsforbattling-a-brainfuck-tournament

by John Doe

JavaScript

var nchars = 30;
var nbrack = 10;
var alphab = "+ - < >".split(' ');
var s = [];
for(var i=0;i<nchars;i++){
    s.push(alphab[(Math.random()*alphab.length)|0]);
}
var ind1,ind2;
for(var i=0;i<nbrack;i++){
    ind1 = (s.length*Math.random())|0;
    s.splice(ind1,0,'[');
    ind2 = ((s.length-ind1-1)*Math.random())|0 + ind1;
    s.splice(ind2,0,']');
}
s = s.join('')
for(var i=0;i<Math.max(nchars,nbrack);i++){//remove useless stuff
    s=s.replace('[]','');
    s=s.replace('+-','+');
    s=s.replace('-+','-');
    s=s.replace('<>','');
    s=s.replace('><','');
}
alert(s);