using Lib; using ModInt = Lib.StaticModInt; 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.Functions; using static Lib.OutputLib; public class Solver { const bool MultiTestCase = false; void Solve() { int n = ri; ReadArray(out int[] a, n); for (int i = 0; i < n; i++) if (a[i] > 0) a[i]--; var f = new bool[n]; for (int i = 0; i < n; i++) if (a[i] >= 0) f[a[i]] = true; var cnt = new int[n]; for (int i = 0; i < n; i++) if (!f[i]) cnt[i]++; for (int i = 0; i < n - 1; i++) cnt[i + 1] += cnt[i]; var fact = new ModFact(n); ModInt ans = 0; int m = -1; int c = 0; for (int i = 0; i < n; i++) { if (a[i] >= 0) { if (a[i] > m) ans += fact.Binom(cnt[a[i]], c) * fact.Fact(c) * fact.Fact(cnt[^1] - c); Chmax(ref m, a[i]); } else { c++; ModInt v = fact.Binom(cnt[^1], c); if (m >= 0) v -= fact.Binom(cnt[m], c); ans += v * fact.Fact(c - 1) * fact.Fact(cnt[^1] - c); } } 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 static class Functions{[MethodImpl(256)]public static int Popcount(ulong x){x=(x&0x5555555555555555UL)+((x>>1)&0x5555555555555555UL);x=(x&0x3333333333333333UL)+((x>>2)&0x3333333333333333UL);x=(x&0x0f0f0f0f0f0f0f0fUL)+((x>>4)&0x0f0f0f0f0f0f0f0fUL);x=(x&0x00ff00ff00ff00ffUL)+((x>>8)&0x00ff00ff00ff00ffUL);x=(x&0x0000ffff0000ffffUL)+((x>>16)&0x0000ffff0000ffffUL);x=(x&0x00000000ffffffffUL)+((x>>32)&0x00000000ffffffffUL);return(int)x;}[MethodImpl(256)]public static int Popcount(long x){x=(x&0x5555555555555555L)+((x>>1)&0x5555555555555555L);x=(x&0x3333333333333333L)+((x>>2)&0x3333333333333333L);x=(x&0x0f0f0f0f0f0f0f0fL)+((x>>4)&0x0f0f0f0f0f0f0f0fL);x=(x&0x00ff00ff00ff00ffL)+((x>>8)&0x00ff00ff00ff00ffL);x=(x&0x0000ffff0000ffffL)+((x>>16)&0x0000ffff0000ffffL);x=(x&0x00000000ffffffffL)+((x>>32)&0x00000000ffffffffL);return(int)x;}[MethodImpl(256)]public static int Popcount(int x){x=(x&0x55555555)+((x>>1)&0x55555555);x=(x&0x33333333)+((x>>2)&0x33333333);x=(x&0x0f0f0f0f)+((x>>4)&0x0f0f0f0f);x=(x&0x00ff00ff)+((x>>8)&0x00ff00ff);x=(x&0x0000ffff)+((x>>16)&0x0000ffff);return x;}[MethodImpl(256)]public static int Ctz(long x){if(x==0)return-1;return Popcount((ulong)((x&-x)-1));}[MethodImpl(256)]public static int CeilPow2(int n){int x=0;while((1<a<=b&&b<=c;[MethodImpl(256)]public static int Sign(long x)=>x==0?0:(x<0?-1:1);[MethodImpl(256)]public static int Sign(double x)=>x==0?0:(x<0?-1:1);[MethodImpl(256)]public static int DigitSum(long n,int d=10){long s=0;while(n>0){s+=n%d;n/=d;}return(int)s;}[MethodImpl(256)]public static long Floor(long a,long b)=>a>=0?a/b:(a+1)/b-1;[MethodImpl(256)]public static long Ceil(long a,long b)=>a>0?(a-1)/b+1:a/b;[MethodImpl(256)]public static int Gcd(int a,int b)=>b==0?a:Gcd(b,a%b);[MethodImpl(256)]public static uint Gcd(uint a,uint b)=>b==0?a:Gcd(b,a%b);[MethodImpl(256)]public static long Gcd(long a,long b)=>b==0?a:Gcd(b,a%b);[MethodImpl(256)]public static ulong Gcd(ulong a,ulong b)=>b==0?a:Gcd(b,a%b);[MethodImpl(256)]public static(long x,long y,long g)ExtGcd(long a,long b){if(b==0)return(Sign(a),0,Math.Abs(a));long c=SafeMod(a,b);var(x2,y2,g)=ExtGcd(b,c);long x=SafeMod(y2,b);long y=(g-a*x)/b;return(x,y,g);}[MethodImpl(256)]public static void Swap(ref int x,ref int y){x^=y;y^=x;x^=y;}[MethodImpl(256)]public static void Swap(ref long x,ref long y){x^=y;y^=x;x^=y;}[MethodImpl(256)]public static void Swap(ref T x,ref T y){T t=y;y=x;x=t;}[MethodImpl(256)]public static T Clamp(T x,T l,T r)where T:IComparable =>x.CompareTo(l)<=0?l:(x.CompareTo(r)<=0?x:r);[MethodImpl(256)]public static T Clamp(ref T x,T l,T r)where T:IComparable =>x=x.CompareTo(l)<=0?l:(x.CompareTo(r)<=0?x:r);[MethodImpl(256)]public static void Chmin(ref T x,T y)where T:IComparable{if(x.CompareTo(y)>0)x=y;}[MethodImpl(256)]public static void Chmax(ref T x,T y)where T:IComparable{if(x.CompareTo(y)<0)x=y;}[MethodImpl(256)]public static int LowerBound(long[]arr,long val,int l=-1,int r=-1)=>LowerBound(arr.AsSpan(),t=>Sign(t-val),l,r);[MethodImpl(256)]public static int LowerBound(int[]arr,int val,int l=-1,int r=-1)=>LowerBound(arr.AsSpan(),t=>t-val,l,r);[MethodImpl(256)]public static int LowerBound(T[]arr,T val,int l=-1,int r=-1)where T:IComparable =>LowerBound(arr.AsSpan(),t=>t.CompareTo(val),l,r);[MethodImpl(256)]public static int LowerBound(T[]arr,Funccomp,int l=-1,int r=-1)=>LowerBound(arr.AsSpan(),comp,l,r);[MethodImpl(256)]public static int LowerBound(Spandata,Funccomp,int l=-1,int r=-1){if(data.Length==0)return-1;if(l==-1)l=0;if(r==-1)r=data.Length;while(l(T[]arr,T geq,T lt,int l=-1,int r=-1)where T:IComparable =>Math.Max(0,LowerBound(arr.AsSpan(),t=>t.CompareTo(lt),l,r)-LowerBound(arr.AsSpan(),t=>t.CompareTo(geq),l,r));[MethodImpl(256)]public static string ToBase2(long v,int digit=-1){if(digit==-1){digit=0;while((v>>digit)>0)digit++;}var c=new string[digit];for(int i=0;i>i)&1)==0?"0":"1";return string.Join("",c);}[MethodImpl(256)]public static string ToBaseN(long v,int n,int digit=-1){if(digit==-1){digit=0;long pow=1;while(v>=pow){digit++;pow*=n;}}var c=new int[digit];for(int i=0;i[n];for(int i=0;i();for(int i=0;i=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=0;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;byte b=0;var ng=false;do b=Read();while(b!='-'&&(b<'0'||'9'double.Parse(Scan());}} namespace Lib{public class ModFactwhere TMod:struct,IStaticMod{static StaticModInt[]fact;static StaticModInt[]factinv;static StaticModInt[]inv;public ModFact(long n){if(fact==null){fact=new StaticModInt[n+1];factinv=new StaticModInt[n+1];inv=new StaticModInt[n+1];fact[0]=1;for(long i=0;i0;i--)factinv[i-1]=factinv[i]*i;for(long i=1;i<=n;i++)inv[i]=fact[i-1]*factinv[i];}else if(fact.Length<=n)Resize(n);}static void Resize(long n){int m=fact.Length;n=Math.Max(n,m*2);Array.Resize(ref fact,(int)n+1);Array.Resize(ref factinv,(int)n+1);Array.Resize(ref inv,(int)n+1);for(long i=m-1;im;i--)factinv[i-1]=factinv[i]*i;for(long i=m;i<=n;i++)inv[i]=fact[i-1]*factinv[i];}[MethodImpl(256)]public StaticModIntFact(long n){if(fact.Length<=n)Resize(n);return fact[n];}[MethodImpl(256)]public StaticModIntFactInv(long n){if(fact.Length<=n)Resize(n);return factinv[n];}[MethodImpl(256)]public StaticModIntInv(long n){if(n==0)throw new DivideByZeroException();if(fact.Length<=n)Resize(n);return inv[n];}[MethodImpl(256)]public StaticModIntBinom(long n,long k){if(n<0)return 0;if(n==0)return k==0?1:0;if(k<0||nBinomInv(long n,long k){if(n<0)throw new DivideByZeroException();if(0<=k&&k<=n){if(fact.Length<=n)Resize(n);return factinv[n]*fact[k]*fact[n-k];}throw new DivideByZeroException();}[MethodImpl(256)]public StaticModIntMultinom(long n,long k1,long k2){if(n<0)return 0;if(n==0)return k1==0&&k2==0?1:0;long k0=n-k1-k2;if(k0<0||k0>n)return 0;if(k1<0||k1>n)return 0;if(k2<0||k2>n)return 0;if(fact.Length<=n)Resize(n);return fact[n]*factinv[k0]*factinv[k1]*factinv[k2];}[MethodImpl(256)]public StaticModIntMultinom(long n,params long[]ks){if(n<0)return 0;long k0=n;foreach(var k in ks)k0-=k;if(k0<0||k0>n)return 0;if(fact.Length<=n)Resize(n);StaticModIntret=fact[n]*factinv[k0];for(int i=0;in)return 0;ret*=factinv[k];}return ret;}}} namespace Lib{public interface IStaticMod{uint Mod{get;}bool IsPrime{get;}}public readonly struct Mod1000000007:IStaticMod{public uint Mod=>1000000007;public bool IsPrime=>true;}public readonly struct Mod998244353:IStaticMod{public uint Mod=>998244353;public bool IsPrime=>true;}public readonly struct StaticModInt:IEquatable>where T:struct,IStaticMod{internal readonly uint _v;private static readonly T op=default;public int Value=>(int)_v;public static int Mod=>(int)op.Mod;public static StaticModIntZero=>default;public static StaticModIntOne=>new StaticModInt(1u);[MethodImpl(256)]public static StaticModIntRaw(int v){var u=unchecked((uint)v);return new StaticModInt(u);}[MethodImpl(256)]public StaticModInt(long v):this(Round(v)){}[MethodImpl(256)]public StaticModInt(ulong v):this((uint)(v%op.Mod)){}[MethodImpl(256)]private StaticModInt(uint v)=>_v=v;[MethodImpl(256)]private static uint Round(long v){var x=v%op.Mod;if(x<0)x+=op.Mod;return(uint)x;}[MethodImpl(256)]public static StaticModIntoperator ++(StaticModIntv){var x=v._v+1;if(x==op.Mod)x=0;return new StaticModInt(x);}[MethodImpl(256)]public static StaticModIntoperator --(StaticModIntv){var x=v._v;if(x==0)x=op.Mod;return new StaticModInt(x-1);}[MethodImpl(256)]public static StaticModIntoperator+(StaticModIntlhs,StaticModIntrhs){var v=lhs._v+rhs._v;if(v>=op.Mod)v-=op.Mod;return new StaticModInt(v);}[MethodImpl(256)]public static StaticModIntoperator-(StaticModIntlhs,StaticModIntrhs){unchecked{var v=lhs._v-rhs._v;if(v>=op.Mod)v+=op.Mod;return new StaticModInt(v);}}[MethodImpl(256)]public static StaticModIntoperator*(StaticModIntlhs,StaticModIntrhs)=>new StaticModInt((uint)((ulong)lhs._v*rhs._v%op.Mod));[MethodImpl(256)]public static StaticModIntoperator/(StaticModIntlhs,StaticModIntrhs)=>new StaticModInt((uint)((ulong)lhs._v*Inv(rhs._v)%op.Mod));[MethodImpl(256)]public static StaticModIntoperator+(StaticModIntv)=>v;[MethodImpl(256)]public static StaticModIntoperator-(StaticModIntv)=>new StaticModInt(v._v==0?0:op.Mod-v._v);[MethodImpl(256)]public static bool operator==(StaticModIntlhs,StaticModIntrhs)=>lhs._v==rhs._v;[MethodImpl(256)]public static bool operator!=(StaticModIntlhs,StaticModIntrhs)=>lhs._v!=rhs._v;[MethodImpl(256)]public static implicit operator StaticModInt(int v)=>new StaticModInt(v);[MethodImpl(256)]public static implicit operator StaticModInt(uint v)=>new StaticModInt((long)v);[MethodImpl(256)]public static implicit operator StaticModInt(long v)=>new StaticModInt(v);[MethodImpl(256)]public static implicit operator StaticModInt(ulong v)=>new StaticModInt(v);[MethodImpl(256)]public static implicit operator long(StaticModIntv)=>v._v;[MethodImpl(256)]public static implicit operator ulong(StaticModIntv)=>v._v;[MethodImpl(256)]public StaticModIntPow(long n){var x=this;var r=new StaticModInt(1U);if(n<0)(x,n)=(x.Inv(),-n);while(n>0){if((n&1)>0)r*=x;x*=x;n>>=1;}return r;}[MethodImpl(256)]public StaticModIntInv()=>new StaticModInt(Inv(_v));[MethodImpl(256)]static ulong Inv(ulong x){long u=op.Mod,xu=1,yu=0,v=(long)x,xv=0,yv=1;while(v!=0){long w=SafeMod(u,v);long q=(u-w)/v;long xw=xu-xv*q;long yw=yu-yv*q;u=v;xu=xv;yu=yv;v=w;xv=xw;yv=yw;}return(ulong)(yu<0?yu+op.Mod:yu);}[MethodImpl(256)]static long SafeMod(long x,long m){long r=x%m;if(r<0)r+=m;return r;}[MethodImpl(256)]public override string ToString()=>_v.ToString();[MethodImpl(256)]public string ToString(string format,IFormatProvider formatProvider)=>_v.ToString(format,formatProvider);[MethodImpl(256)]public override bool Equals(object?obj)=>obj is StaticModIntm&&Equals(m);[MethodImpl(256)]public bool Equals(StaticModIntother)=>_v==other._v;[MethodImpl(256)]public override int GetHashCode()=>_v.GetHashCode();}} 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=" "){for(int i=0;i(T[][]a,Funcmap,string sep=" "){for(int i=0;imap(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