using Lib; using System; using System.Collections.Generic; using System.Diagnostics; using System.IO; using System.Linq; using System.Runtime.CompilerServices; using System.Text; using static Lib.OutputLib; public class Solver { const bool MultiTestCase = false; void Solve() { int n = ri, m = ri; // sum[i:1~n]f_i=f_(n+2)-1 // f_(r+2)-f_(l+1) : mul of n // f_(r+2)-f_(l+1) <= f_m // r+2<=m なら下は ok // 2<=l'm のとき (i.e. r>=m-1) // 元の総和表示を思い出すと (l,r)=(m-2,m-1),(m-1,m-1),(m,m) しかない // 周期はだいぶ小さいらしい long ans = 0; if (n == 1) { ans += (long)(m - 2) * (m - 1) / 2; ans++; if (m - 1 >= 1) ans++; if (m - 2 >= 1) ans++; } else { int p; { var c0 = new long[n]; { int x = 1, y = 1; for (p = 1; ; p++) { c0[x]++; if ((x, y) == (0, 1)) break; (x, y) = (y, (x + y) % n); } } int k = m + 1; var c = new long[n]; for (int i = 0; i < n; i++) c[i] += c0[i] * (k / p); k %= p; { int x = 0, y = 1; for (int i = 0; i < k; i++) { c[x]++; (x, y) = (y, (x + y) % n); } } c[0]--; c[1]--; for (int i = 0; i < n; i++) ans += c[i] * (c[i] - 1) / 2; } int f(int k) { k %= p; int x = 0, y = 1; for (int i = 0; i < k; i++) (x, y) = (y, (x + y) % n); return x; } if (f(m) == 0) ans++; if (m - 1 >= 1 && f(m - 1) == 0) ans++; if (m - 2 >= 1 && (f(m - 1) + f(m - 2)) % n == 0) ans++; } Write(ans); } #pragma warning disable CS0162 public Solver() { if (!MultiTestCase) Solve(); else for (int t = ri; t > 0; t--) Solve(); } #pragma warning restore CS0162 const int IINF = 1 << 30; const long INF = 1L << 60; int ri { [MethodImpl(256)] get => (int)sc.Integer(); } long rl { [MethodImpl(256)] get => sc.Integer(); } uint rui { [MethodImpl(256)] get => (uint)sc.UInteger(); } ulong rul { [MethodImpl(256)] get => sc.UInteger(); } double rd { [MethodImpl(256)] get => sc.Double(); } string rs { [MethodImpl(256)] get => sc.Scan(); } string rline { [MethodImpl(256)] get => sc.Line(); } public StreamScanner sc = new StreamScanner(Console.OpenStandardInput()); void ReadArray(out int[] a, int n) { a = new int[n]; for (int i = 0; i < a.Length; i++) a[i] = ri; } void ReadArray(out long[] a, int n) { a = new long[n]; for (int i = 0; i < a.Length; i++) a[i] = rl; } void ReadArray(out T[] a, int n, Func read) { a = new T[n]; for (int i = 0; i < a.Length; i++) a[i] = read(); } void ReadArray(out T[] a, int n, Func read) { a = new T[n]; for (int i = 0; i < a.Length; i++) a[i] = read(i); } } static class Program { static public void Main(string[] args) { SourceExpander.Expander.Expand(); Console.SetOut(new StreamWriter(Console.OpenStandardOutput()) { AutoFlush = false }); new Solver(); Console.Out.Flush(); } } #region Expanded by https://github.com/kzrnm/SourceExpander namespace Lib{public partial class StreamScanner{public StreamScanner(Stream stream){str=stream;}private readonly Stream str;private readonly byte[]buf=new byte[1024];private int len,ptr;public bool isEof=false;public bool IsEndOfStream{get{return isEof;}}[MethodImpl(256)]private byte Read(){if(isEof)throw new EndOfStreamException();if(ptr>=len){ptr=0;if((len=str.Read(buf,0,1024))<=0){isEof=true;return 0;}}return buf[ptr++];}[MethodImpl(256)]public char Char(){byte b;do b=Read();while(b<33||126=33&&b<=126;b=(char)Read())sb.Append(b);return sb.ToString();}[MethodImpl(256)]public long Integer(){long ret=0;var ng=false;byte b;do b=Read();while(b!='-'&&(b<'0'||'9'double.Parse(Scan());}} namespace Lib{public static class OutputLib{[MethodImpl(256)]public static void WriteJoin(string s,IEnumerablet)=>Console.WriteLine(string.Join(s,t));[MethodImpl(256)]public static void WriteMat(T[,]a,string sep=" "){int sz1=a.GetLength(0),sz2=a.GetLength(1);var b=new T[sz2];for(int i=0;i(T[][]a,string sep=" "){foreach(var ar in a)WriteJoin(sep,ar);}[MethodImpl(256)]public static void WriteMat(T[][]a,Funcmap,string sep=" "){foreach(var ar in a)WriteJoin(sep,ar.Select(x=>map(x)));}[MethodImpl(256)]public static void Write(object t)=>Console.WriteLine(t.ToString());[MethodImpl(256)]public static void Write(params object[]arg)=>Console.WriteLine(string.Join(" ",arg.Select(x=>x.ToString())));[MethodImpl(256)]public static void Write(string str)=>Console.WriteLine(str);[MethodImpl(256)]public static void WriteFlush(object t){Console.WriteLine(t.ToString());Console.Out.Flush();}[MethodImpl(256)]public static void WriteError(object t)=>Console.Error.WriteLine(t.ToString());[MethodImpl(256)]public static void Flush()=>Console.Out.Flush();[MethodImpl(256)]public static void YN(bool t)=>Console.WriteLine(t?"YES":"NO");[MethodImpl(256)]public static void Yn(bool t)=>Console.WriteLine(t?"Yes":"No");[MethodImpl(256)]public static void yn(bool t)=>Console.WriteLine(t?"yes":"no");[MethodImpl(256)]public static void DeleteLine()=>Console.Write("\x1b[1A\x1b[2K");[MethodImpl(256)]public static void ProgressBar(long now,long total,int blocks=50){int x=(int)((2*now*blocks+1)/(2*total));Console.Write($"\x1b[G[\x1b[42m{string.Concat(Enumerable.Repeat("_",x))}\x1b[0m{string.Concat(Enumerable.Repeat("_",blocks-x))}] : {now} / {total}");}}} namespace SourceExpander{public class Expander{[Conditional("EXP")]public static void Expand(string inputFilePath=null,string outputFilePath=null,bool ignoreAnyError=true){}public static string ExpandString(string inputFilePath=null,bool ignoreAnyError=true){return "";}}} #endregion Expanded by https://github.com/kzrnm/SourceExpander