SOURCE

var arr=[3,44,38,5,47,15,36,26,27,2,46,4,19,50,48];
function maxDig(arr,length){
    var max=arr[0];
    for(var i=1;i<arr.length;i++){
        if(max<arr[i])
        max=arr[i];
    }
    var d=1,p=10;
    while(max>=p){
        max/=p;
        d++;
    }
    return d;
}