题解 | #字符个数统计#

let str; while(str = readline()) { let arr = str.split(''); let o = {}; arr.forEach(v=>{ if(!o[v.charCodeAt(0)] && v.charCodeAt(0) >=0 && v.charCodeAt(0) <= 127) { o[v.charCodeAt(0)] = true; } }) console.log(Object.keys(o).length); }