using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace MyString
{
    class MyString
    {
        public string mystring
        {
            get;
            set;
        }
        public void upperTOlower()//大写转换为小写（功能同string.ToLower）
        {
            char[] str = mystring.ToCharArray();
            for (int i = 0; i < str.Length; i++)
            {
                if (str[i] <= 'Z'&&str[i]>='A')
                {
                    int v = 'a' - 'A';
                    int m = (int)str[i] + v;
                    str[i] = (char)m;
                }
                Console.Write(str[i]);
            }
        }
        public void lowerTOupper()//小写转换为大写（功能同string.ToUpper）
        {
            char[] str = mystring.ToCharArray();
            for (int i = 0; i < str.Length; i++)
            {
                if (str[i] <= 'z' && str[i] >= 'a')
                {
                    int v = 'a' - 'A';
                    int m = (int)str[i] - v;
                    str[i] = (char)m;
                }
                Console.Write(str[i]);
            }
        }
    }
    class Program
    {
        static void Main(string[] args)
        {
            MyString s = new MyString();
            s.mystring = Console.ReadLine();
            s.lowerTOupper();
            Console.ReadKey();
        }
    }
}