js统计字符串，并且判断出现次数最多的

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    <meta charset="UTF-8">
    <title>Document</title>
    <script>
        var s="123123189273893724901734891379486452098524345";
        var fres={};  //用来记录所有的字符的出现频次
        var mostFreqChar=''; //用来记录最大频次的字符
        var key;
        for(var i=0;i<s.length;i++){
            var char=s[i];
            if(!fres[char]){
                fres[char]=0;
            }
            fres[char]++;
         }

        for(key in fres){
            if(mostFreqChar==''||fres[key]>fres[mostFreqChar]){
                mostFreqChar=key;
            }
         }
        console.log(mostFreqChar);
        console.log(fres[mostFreqChar]);

    </script>
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