heap Sort

function heapSort(t){
    _buildHeap(t);
    var len = t.length-2;
    while(len>=1){
        _heapSwap2(t, 0, len);
        temp = t[0];
        t[0] = t[len];
        t[len] = temp;
        len--;
    }
}
function _heapSwap2(t, i, l){
    var i1 = 2*i+1, i2 =2*i+2, maxi;
    if( i2>l ){
        if( i1>l )
            return;
        else
            maxi = i1;
    }else{
        if( t[i1]<t[i2] )
            maxi = i2;
        else
            maxi = i1;
    }
    if( t[i]<t[maxi] ){
        var temp = t[i];
        t[i] = t[maxi];
        t[maxi] = temp;
        _heapSwap2(t, maxi, l);
    }
}
function _heapSwap(t, i){
    while( i!=0 ){
        j = Math.ceil(i/2)-1;
        if( t[j]<t[i] ){
            var temp = t[i];
            t[i] = t[j];
            t[j] = temp;
            i = j;
        }else
            i=0;
    }
}
function _buildHeap(t){
    len = t.length;
    i = 0;
    while( i<len ){
        _heapSwap(t, i);
        i++;
    }
    var temp = t[0];
    t[0] = t[len-1];
    t[len-1] = temp;
}