判断一个字符串中,每个元素出现的次数,并返回一个对象来统计出现的元素,以及次数
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<body>
<script>
var str = 'abccbaaab'
var obj = {}
for(var i =0 ; i < str.length ; i++){
if(obj[str.charAt(i)]){
obj[str.charAt(i)] ++
}else{
obj[str.charAt(i)] = 1
}
}
console.log(obj)
</script>
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