Three Digit Sum Using Tuple in C#

Introduction

In this article, we will be discussing an algorithm which returns possible (no. of pairs) digit pairs that are equal to a given number (6) using Tuple class.

Prerequisite

Suppose we pass a list of numbers List<int> { 1 , 2 , 3 , 4 , 5 , 6 } with 6 as a sum, The possible pairs should be :

• 0 0  3  ( 1 + 1 + 4 ) = 6
• 0 1  2  ( 1 + 2 + 3 ) = 6
• 0 2  1  ( 1 + 3 + 2 ) = 6
• 0 3  0  ( 1 + 4 + 1 ) = 6
• 1 0  2  ( 2 + 1 + 3 ) = 6
• 1 1  1  ( 2 + 2 + 2 ) = 6
• 1 2  0  ( 2 + 3 + 1 ) = 6
• 2 0  1  ( 3 + 1 + 2 ) = 6
• 2 1  0  ( 3 + 2 + 1 ) = 6
• 3 0  0  ( 4 + 1 + 1 ) = 6

How?

• The following is the basic function which we will implement in this article.
  

  public static List<Tuple<int,int,int>> PairsOfThreeDigitSum(IList<int> lstInt, int sum)
  {
      // Implementation
  }

• Above function which is return wist of Tuple<int,int,int> actually will contain three digit pairs that are equal to given sum.

• We will iterate through for loop and check if the sum of the list is equal to the to sum we gave.
  

  for (int i=0;i<lstInt.Count;i++)
  {
      for (int i=0;i<lstInt.Count;i++)
      {
          for (int i=0;i<lstInt.Count;i++)
          {
              if (sum == (lstInt[i] + lstInt[j] + lstInt[k]))
              {
                   pairs.Add(Tuple.Create<int,int,int>>(I , j, k);
              }
          }
      }
  }

• If condition becomes true it means this is the pair in which sum is equal to the sum we gave. I will store that pair index into our List of Tuples by Add() method
  

  if (sum == (lstInt[i] + lstInt[j] + lstInt[k]))
  {
     pairs.Add(Tuple.Create<int,int,int>>(I , j, k);
  }

• Loop iterates until the count of elements in the list; and finally it will return the pairs which hold three digits pairs as with,       

  return pairs;

• The below is the function which will do the same.

Final Code

The below is the code and output window.

class Program
{
        static void Main(string[] args)
        {
            var lst = new List<int> { 1, 2, 3, 4, 5 };
            int sum = 6;

            List<Tuple< int, int, int >> pairs = PairsOfThreeDigitSum(lst, sum);

            Console.WriteLine("Possible pairs of three digits whose sum are equivalent to {0} ", sum);

            foreach (var _pairs in pairs)
            {
                Console.WriteLine("{0} {1} {2}", _pairs.Item1, _pairs.Item2, _pairs.Item3);
            }

            Console.ReadKey(true);
        }

        public static List<Tuple<int,int,int>> airsOfThreeDigitSum(IList<int>        lstInt, int sum)
        {
           List<Tuple<int,int,int>> pairs = new List<Tuple<int,int,int>>();
           for (int i=0;i<lstInt.Count;i++)
           {
               for (int i=0;i<lstInt.Count;i++)
               {
                  for (int i=0;i<lstInt.Count;i++)
                  {
                      if (sum == (lstInt[i] + lstInt[j] + lstInt[k]))
                      {
                         pairs.Add(Tuple.Create<int,int,int>>(I , j, k);
                      }
                  }
               }
           }
           return pairs;
        }
}

Output

Summary

In this article, I discussed how we can create a method that returns Three Digit Pairs using Tuple class in C#. 

I hope you liked my article.:)