[Deff]

var arr=[
'(((1+2)+3)*10-(3-1)))/10=',
'(((1+2)+3)*10-(3-1))/10=',
'(((1+)2)+3)*10-(3-1))/10=',
'(((1+2()+3)*10-(3-1))/10='
]

function rep (a){
  var c=a;
  var b=true;
  while (a.search(/[\(\)]/g)!= -1&&b) {
    a = a.replace(/\([^\(\)]+\)/g,'$');//alert(a)
    b = a.split(/\(|\)/).length!=2 && a.replace(/\(\)/g,'')==a;
  }
if(b){b=eval(c.replace("=",""))}
return b;
}

for(var i in arr){
alert('N='+i+'\n'+arr[i]+'  ' +rep (arr[i]+';'));
}