Code:
#include <cstdio> #include <algorithm> #include <cmath> #include <cstring> #define setIO(s) freopen(s".in","r",stdin) #define maxn 200000 #define pi 3.1415926535898 using namespace std; int len=1,l,r[maxn<<1]; int ans[maxn]; char str1[maxn],str2[maxn]; struct Cpx{ double x,y; Cpx(double t1=0,double t2=0){x=t1,y=t2;} }A[maxn<<1],B[maxn<<1],C[maxn<<1],BB[maxn<<1]; Cpx operator+(Cpx a,Cpx b){ return Cpx(a.x+b.x,a.y+b.y);} Cpx operator-(Cpx a,Cpx b){ return Cpx(a.x-b.x,a.y-b.y);} Cpx operator*(Cpx a,Cpx b){ return Cpx(a.x*b.x-a.y*b.y,a.x*b.y+a.y*b.x);} void FFT(Cpx *a,int n,int flag){ for(int i=0;i<n;++i) if(i<r[i]) swap(a[i],a[r[i]]); for(int mid=1;mid<n;mid<<=1){ Cpx wn(cos(pi/mid),flag*sin(pi/mid)),x,y; for(int j=0;j<n;j+=(mid<<1)){ Cpx w(1,0); for(int k=0;k<mid;++k){ x=a[j+k],y=w*a[j+mid+k]; a[j+k]=x+y,a[j+mid+k]=x-y; w=w*wn; } } } } int main(){ //setIO("input"); int n; scanf("%d",&n); for(int i=0;i<n;++i) scanf("%lf",&A[i].x),scanf("%lf",&BB[i].x); for(int i=0;i<n;++i) B[i].x=BB[n-i-1].x; while(len<n+n) len<<=1,++l; for(int i=0;i<len;++i) r[i]=(r[i>>1]>>1)|((i&1)<<(l-1)); FFT(A,len,1),FFT(B,len,1); for(int i=0;i<=len;++i) C[i]=A[i]*B[i]; FFT(C,len,-1); for(int i=0;i<=len;++i) ans[i]=(int)(C[i].x/len+0.5); for(int i=0;i<n;++i) printf("%d\n",ans[i+n-1]); return 0; }