题解 | #字符串加解密#

let str1 = readline();
let str2 = readline();
function jiami(str) {
    let result = '';
    for(let i = 0; i < str.length; i++) {
        let s = str[i];
        // 字母
        if(/[A-Za-z]/.test(s)) {
            let ascii = s.charCodeAt(0);
            // Z -> A, z -> a
            if(ascii == 90) {
                ascii = 65;
            } else if(ascii == 122) {
                ascii = 97;
            } else {
                ascii += 1;
            }
            s = String.fromCharCode(ascii);
            if(ascii < 97) {
                s = s.toLocaleLowerCase();
            } else {
                s = s.toLocaleUpperCase();
            }
        }
        // 数字
        if(/[0-9]/.test(s)) {
            if(s == 9) {
                s = 0;
            } else {
                s = +s + 1;
            }
        }
        result += s;
    }
    return(result);
}
function jiemi(str) {
    let result = '';
    for(let i = 0; i < str.length; i++) {
        let s = str[i];
        // 字母
        if(/[A-Za-z]/.test(s)) {
            let ascii = s.charCodeAt(0);
            // A -> Z, a -> z
            if(ascii == 65) {
                ascii = 90;
            } else if(ascii == 97) {
                ascii = 122;
            } else {
                ascii -= 1;
            }
            s = String.fromCharCode(ascii);
            if(ascii < 97) {
                s = s.toLocaleLowerCase();
            } else {
                s = s.toLocaleUpperCase();
            }
        }
        // 数字
        if(/[0-9]/.test(s)) {
            if(s == 0) {
                s = 9;
            } else {
                s = +s - 1;
            }
        }
        result += s;
    }
    return(result);
}
console.log(jiami(str1));
console.log(jiemi(str2));