The JavaScript implementation counts the most frequently occurring characters in a string and the number of occurrences

"Figure out what character appears the most in a string, and how many times?"

Seeing this requirement, I think most people should first think of converting to an array and then doing some processing. Of course, it can solve the problem. Then, here is a clever algorithm design, which can solve the problem quickly without converting to an array.

var str = "adadfdfseffserfefsefseeffffftsdg";

var maxLength = 0;

var result = "";

while(str!=''){

    oldStr = str;

    getStr = str.charAt(0);

    str = str.replace(new RegExp(getStr,"g"),"");

    if( oldStr.length-str.length > maxLength){

        maxLength = oldStr.length-str.length;

        result = getStr + "=" + maxLength;

    }

}

alert(result);