题解 | #字符个数统计#

while(line = readline()) {
    var str = line.trim()
    var length = str.length
    var tempMap = {}
    for (var i = 0; i < length; i++) {
        var ch = str[i], charCode = ch.charCodeAt(0)
        if (charCode >=0 && charCode <= 127) {
            tempMap[ch] = 1
        }
    }
    console.log(Object.keys(tempMap).length)
}