using System; using System.Collections; using System.Collections.Generic; using System.Linq; using System.Text; using System.IO; class TEST{ static void Main(){ Sol mySol =new Sol(); mySol.Solve(); } } class Sol{ public void Solve(){ long mod = (long)1e9 + 7; long[] Fact = new long[N+1]; Fact[0] = 1; for(int i=1;i<=N;i++){ Fact[i] = Fact[i-1] * i; Fact[i] %= mod; } if(K==0){ Console.WriteLine(Fact[N]); return; } Array.Sort(A); int[] bc = new int[N]; int tot = N; long ans = 1; for(int i=0;i0) inc -= A[i-1]; int cnt = 0; for(int j=0;j> j)&1) == 1){ bc[j]++; cnt++;} if(bc[j]>1){ Console.WriteLine(0); return; } } ans *= Fact[cnt]; ans %= mod; tot -= cnt; } ans *= Fact[tot]; ans %= mod; Console.WriteLine(ans); } int N,K; long[] A; public Sol(){ using(var r = new FastIn()){ N = r.ReadInt(); K = r.ReadInt(); if(K>0){ A = new long[K]; for(int i=0;iint.Parse(e));} static long[] rla(char sep=' '){return Array.ConvertAll(Console.ReadLine().Split(sep),e=>long.Parse(e));} static double[] rda(char sep=' '){return Array.ConvertAll(Console.ReadLine().Split(sep),e=>double.Parse(e));} } class FastIn:IDisposable { int Size; byte[] Mem; int ptr; int rsize; bool unfinished; Stream stdin; void Init(int n) { Size = n; Mem = new byte[Size]; rsize=(stdin=Console.OpenStandardInput()).Read(Mem, 0, Size); ptr = 0; unfinished=(rsize == Size); } void Next() { if (unfinished == false) return; rsize=stdin.Read(Mem, 0, Size); ptr = 0; unfinished = (rsize == Size); } ~FastIn(){ stdin.Dispose(); } void IDisposable.Dispose(){ stdin.Dispose(); } public void Dispose(){ stdin.Dispose(); } public FastIn() { Init(100000); } public FastIn(int n) { Init(n); } public int ReadInt() { int ret = 0; int sig = 1; while (ptr < rsize && Mem[ptr] != ' ' && Mem[ptr] != '\n' && Mem[ptr] != '\r' ) { if(ret==0 && Mem[ptr] == '-'){ sig *= -1; ptr++; continue; } ret = ret * 10 + Mem[ptr++] - '0'; if (ptr == Size) Next(); } while (ptr < rsize && (Mem[ptr] == ' ' || Mem[ptr] == '\n' || Mem[ptr] == '\r') ) { ptr++; if (ptr == Size) Next(); } return ret*sig; } public uint ReadUint() { uint ret = 0; uint sig = 1; while (ptr < rsize && Mem[ptr] != ' ' && Mem[ptr] != '\n' && Mem[ptr] != '\r' ) { ret = ret * 10 + Mem[ptr++] - '0'; if (ptr == Size) Next(); } while (ptr < rsize && (Mem[ptr] == ' ' || Mem[ptr] == '\n' || Mem[ptr] == '\r') ) { ptr++; if (ptr == Size) Next(); } return ret*sig; } public long ReadLong() { long ret = 0; long sig = 1; while (ptr < rsize && Mem[ptr] != ' ' && Mem[ptr] != '\n' && Mem[ptr] != '\r' ) { if(ret==0 && Mem[ptr] == '-'){ sig *= -1; ptr++; continue; } ret = ret * 10 + Mem[ptr++] - '0'; if (ptr == Size) Next(); } while (ptr < rsize && (Mem[ptr] == ' ' || Mem[ptr] == '\n' || Mem[ptr] == '\r') ) { ptr++; if (ptr == Size) Next(); } return ret*sig; } public double ReadDouble() { double ret = 0; double sig = 1; bool dot = false; double keta = 0.1; while (ptr < rsize && Mem[ptr] != ' ' && Mem[ptr] != '\n' && Mem[ptr] != '\r' ) { if(ret==0 && Mem[ptr] == '-'){ sig *= -1; ptr++; if (ptr == Size) Next(); continue; } if(Mem[ptr] == '.'){ dot = true; ptr++; if (ptr == Size) Next(); continue; } if(!dot){ ret = ret * 10 + Mem[ptr++] - '0'; if (ptr == Size) Next(); }else{ ret = ret + (Mem[ptr++] - '0')*keta; keta /= 10.0; if (ptr == Size) Next(); } } while (ptr < rsize && (Mem[ptr] == ' ' || Mem[ptr] == '\n' || Mem[ptr] == '\r') ) { ptr++; if (ptr == Size) Next(); } return ret*sig; } public String ReadStr() { //2byte文字はNG StringBuilder sb = new StringBuilder(); while (ptr < rsize && Mem[ptr] != ' ' && Mem[ptr] != '\n' && Mem[ptr] != '\r') { sb.Append((char)Mem[ptr++]); if (ptr == Size && unfinished) Next(); } while (ptr < rsize && (Mem[ptr] == ' ' || Mem[ptr] == '\n' || Mem[ptr] == '\r') ) { ptr++; if (ptr == Size && unfinished) Next(); } return sb.ToString(); } public String ReadLine() { //極力使わない(split/parseするくらいなら上をつかう) StringBuilder sb = new StringBuilder(); while (ptr < rsize && Mem[ptr] != '\n' && Mem[ptr] != '\r') { sb.Append((char)Mem[ptr++]); if (ptr == Size && unfinished) Next(); } while (ptr < rsize && (Mem[ptr] == ' ' || Mem[ptr] == '\n' || Mem[ptr] == '\r')) { ptr++; if (ptr == Size && unfinished) Next(); } return sb.ToString(); } }