using System;
using System.Linq;

namespace MyCompiler {
    class Program {
        public static void Main(string[] args) 
        {
            MinTurns("4089", "5672");
            MinTurns("1111", "1100");
            MinTurns("2391", "4984");
        }
        
        public static void MinTurns(string current, string target)
        {
            int sum = 0;
            foreach(int i in Enumerable.Range(0,current.Length))
            {
                sum += Math.Min(Math.Abs(0- Convert.ToInt32(target[i].ToString())),9 - Convert.ToInt32(target[i].ToString()));
            }
            Console.WriteLine(sum);
        }
    }
}