using System; using System.Collections.Generic; class Program { static string InputPattern = "Input4"; static List GetInputList() { var WillReturn = new List(); if (InputPattern == "Input1") { WillReturn.Add("10000"); WillReturn.Add("5"); } else if (InputPattern == "Input2") { WillReturn.Add("24500"); WillReturn.Add("9"); } else if (InputPattern == "Input3") { WillReturn.Add("1000"); WillReturn.Add("6"); } else { string wkStr; while ((wkStr = Console.ReadLine()) != null) WillReturn.Add(wkStr); } return WillReturn; } static void Main() { Eratosthenes(); List InputList = GetInputList(); ulong N = ulong.Parse(InputList[0]); int M = int.Parse(InputList[1]); //余った金額 int RestVal = (int)(N % (1000 * (ulong)M)); Console.WriteLine(DeriveCombiCnt(M, RestVal / 1000)); } //Aつの袋からBつの袋を選ぶ組み合わせの数を求める static ulong DeriveCombiCnt(int pA, int pB) { if (pA == 0) return 1; pB = Math.Min(pB, pA - pB); var ProdList = new List(); var DeviList = new List(); for (int I = pA; I >= pA - pB + 1; I--) { ProdList.Add(I); } for (int I = 1; I <= pB; I++) { DeviList.AddRange(DeriveSoinsuuArr(I)); } //分母を全てはらってから、総積を1000000000で割った余りを求める for (int I = DeviList.Count - 1; 0 <= I; I--) { for (int J = 0; J <= ProdList.Count - 1; J++) { if (ProdList[J] % DeviList[I] == 0) { ProdList[J] /= DeviList[I]; DeviList.RemoveAt(I); break; } } } ulong WillReturn = 1; ProdList.ForEach(X => WillReturn = (WillReturn * (ulong)X) % 1000000000); return WillReturn; } const int Jyougen = 10000; static int[] SosuuArr; //エラトステネスの篩 static void Eratosthenes() { var CheckArr = new bool[Jyougen + 1]; for (int I = 2; I <= CheckArr.GetUpperBound(0); I++) { CheckArr[I] = true; } for (int I = 2; I <= CheckArr.GetUpperBound(0); I++) { if (I != 2 && I % 2 == 0) continue; if (CheckArr[I]) { for (int J = I * 2; J <= CheckArr.GetUpperBound(0); J += I) { CheckArr[J] = false; } } } var SosuuList = new List(); for (int I = 2; I <= CheckArr.GetUpperBound(0); I++) if (CheckArr[I]) SosuuList.Add(I); SosuuArr = SosuuList.ToArray(); } //素因数分解した素因数の配列を返す static int[] DeriveSoinsuuArr(int pTarget) { if (Array.BinarySearch(SosuuArr, pTarget) >= 0) { return new int[] { pTarget }; } var SoinsuuList = new List(); for (int I = 0; I <= SosuuArr.GetUpperBound(0); I++) { while (pTarget % SosuuArr[I] == 0) { SoinsuuList.Add(SosuuArr[I]); pTarget /= SosuuArr[I]; } if (pTarget == 1) break; } return SoinsuuList.ToArray(); } }