[BOJ] 3040 백설 공주와 일곱 난쟁이

https://www.acmicpc.net/problem/3040

3040번: 백설 공주와 일곱 난쟁이

 

조합 

 

using System;
using System.Linq;

namespace smilejsu
{
    class Program
    {
        private static int[] arr = new int[9];
        
        static void Main(string[] args)
        {
            for (int i = 0; i < 9; i++)
            {
                arr[i] = int.Parse(Console.ReadLine());
            }

            string input = "012345678";
            int combinationLength = 7;
            GenerateCombinations(input, "", combinationLength, 0);
            
        }
        static void GenerateCombinations(string input, string output, int combinationLength, int index)
        {
            //Console.WriteLine("{0}", output);
            
            if (output.Length == combinationLength)
            {
                
                int sum = 0;
                for (int i = 0; i < output.Length; i++)
                {
                    int idx = int.Parse(output[i].ToString()); 
                    sum += arr[idx];
                    //Console.Write("{0} ", idx);
                }
                //Console.WriteLine();
                if (sum == 100)
                {
                    for (int i = 0; i < output.Length; i++)
                    {
                        int idx = int.Parse(output[i].ToString()); 
                        //sum += arr[idx];
                        Console.WriteLine("{0}", arr[idx]);
                    }
                    //Console.WriteLine(output);   
                }
                return;
            }

            if (index >= input.Length)
            {
                return;
            } 
            
            GenerateCombinations(input, output + input[index], combinationLength, index + 1);
            GenerateCombinations(input, output, combinationLength, index + 1);
        }
    }
}