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母函数

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         using namespace std;const double pi=acos(-1);char c;inline void read(int &a){a=0;do c=getchar();while(c<'0'||c>'9');while(c<='9'&&c>='0')a=(a<<3)+(a<<1)+c-'0',c=getchar();}int len=262144;#define com complex
         
          struct Complex_Line{ com*D; inline void Bg(){D=new com[len];} inline com&operator [](int x){ return D[x];}};int rev[300000];void Rader(){ int t=1; while(len>(1<
          
           >1]>>1)|((i&1)<<(t-1));}Complex_Line Rev(Complex_Line a){ Complex_Line res; res.Bg(); for(int i=0;i
           
            =1) printf("%d %d\n",i,(int)(Q+0.5)); return 0;}