题解 | #字符个数统计#
字符个数统计
http://www.nowcoder.com/practice/eb94f6a5b2ba49c6ac72d40b5ce95f50
let str = readline()
let arr = str.split('')
const repeat = array => {
return array.filter((value, index) => {
return array.indexOf(value) === index
})
}
const res = repeat(arr)
console.log(res.length)
