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

namespace Pandigitals
{
    class Program
    {
        public static void Main(string[] args)
        {
            var result = new List<int>();
            var nums = new int[100, 10000];
            for (var i = 1; i <= 99; i++)
                for (var j = 123; j <= 9999; j++)
                {
                    if (GetDiffMyltiply(i, j) && GetRightNums(i) && GetRightNums(j) &&
                        (i.ToString().Length + j.ToString().Length == 5))
                        nums[i, j] = i * j;
                    if (nums[i, j].ToString().Length == 4 && GetDifference(nums[i, j], i, j))
                        result.Add(nums[i, j]);
                }
            Console.WriteLine(result.Distinct().Sum(x=>x));
            Console.ReadKey();
        }

        public static bool GetRightNums(int num)
        {
            var digCount = 0;
            var res = new List<int>();
            var list = new HashSet<int>();
            while (num > 0)
            {
                int mod = num % 10;
                res.Add(mod);
                if (!list.Add(mod) || mod == 0) break;
                num /= 10;
                digCount++;
            }
            return (digCount == res.Count) ? true : false;
        }

        public static bool GetDiffMyltiply(int i, int j)
        {
            var si = i.ToString();
            var sj = j.ToString();
            foreach (var item in si)
                if (sj.Contains(item))
                    return false;
            return true;
        }

        public static bool GetDifference(int num, int i, int j)
        {
            var res = new List<char>();
            var si = i.ToString();
            var sj = j.ToString();
            var snum = num.ToString();
            if (!GetRightNums(num)) return false;
            foreach (var itemI in si)
                foreach (var itemJ in sj)
                {
                    if (snum.Contains(itemI) || snum.Contains(itemJ))
                        return false;
                }
            return true;
        }
    }
}