Polynomial to find inverse of template __ polynomial negation

The concrete concept and the method of solving the inverse element of polynomial see here, this article mainly provides templates.

This article provides a template that retains the 0~ N-n-th term, mod (xn+1) mod (x^{n+1}) under modulo 998244353.

#include <bits/stdc++.h> #define LL long-long using namespace std;
    int Getint () {int I=0,f=1;char C; For (C=getchar (); c!= '-' && (c< ' 0 ' | |
    C> ' 9 '); C=getchar ());
    if (c== '-') F=-1,c=getchar ();
    for (; c>= ' 0 ' &&c<= ' 9 '; C=getchar ()) i= (i<<3) + (i<<1) +c-' 0 ';
return i*f;
const int n=500005,p=998244353,g=3;

int n,a[n],b[n],pos[n],w[n],inv[n];
    int Pow (int x,int y) {int res=1;
    for (; y;y>>=1,x= (LL) x*x%p) if (y&1) res= (LL) res*x%p;
return res;
    } void Init () {int len=1,num=0;
        while (len< (n+1) <<1)) {len<<=1;
        W[++num]=pow (g, (p-1)/len);
    Inv[num]=pow (w[num],p-2); } void NTT (int f[],int len,int on) {for (int i=1;i<len;i++) pos[i]= (i&1)? pos[i>>1]>>1| (
    len>>1):p os[i>>1]>>1;
    for (int i=1;i<len;i++) if (I<pos[i]) swap (f[i],f[pos[i]); for (int i=1,num=1;i<len;i<<=1,num++) {int wn=(On==1?w[num]:inv[num]);
            for (int j=0;j<len;j+= (i<<1)) {int wi=1;
                for (int k=j;k<j+i;k++) {int u=f[k],v= (LL) wi*f[k+i]%p;
                f[k]= (u+v)%p,f[k+i]= (u-v+p)%p;
            Wi= (ll) wi*wn%p;
{}} if (On==-1) for (int i=0;i<len;i++) f[i]= (LL) F[i]*pow len,p-2 (%p);
        } void Poly_inv (int a[],int b[],int deg) {if (deg==1) {B[0]=pow (a[0],p-2);
    Return
    } POLY_INV (A,b, (deg+1) >>1);
    static int tmp[n];
    int len=1;
    while (len< (deg<<1)) len<<=1;
    for (int i=0;i<deg;i++) tmp[i]=a[i];
    for (int i=deg;i<len;i++) tmp[i]=0;
    for (int i= (deg+1) >>1;i<len;i++) b[i]=0;
    NTT (tmp,len,1), NTT (b,len,1);
    for (int i=0;i<len;i++) b[i]= (LL) b[i]* ((LL) tmp[i]*b[i]%p+p)%p)%p;
NTT (b,len,-1);
    int main () {//freopen ("lx.in", "R", stdin);
    N=getint ();
    Init (); for (int i=0;i<=n;i++) A[i]=getint ();
    POLY_INV (a,b,n+1);
    for (int i=0;i<=n;i++) cout<<b[i]<< ';
return 0; }