var s=["jack", "apple", "maven", "hold", "solid", "mark", "moon", "poor", "spark", "live"];

​

var perfect="";

​

s.forEach(function(s){

 s.split("").reduce(function(pos,char){

       var n=perfect.indexOf(char,pos+1);

    if(n<0){

      perfect=perfect.substr(0,pos+1)+char+perfect.substr(pos+1);

    return pos+1;

    }

    return n;

},-1);

})

​

console.log(perfect," improvement of "+s.join("").length/perfect.length*100+" %");