#include using namespace std; #define REP(i,a,b) for(i=a;i'9')break;*x=(*x)*10+k-'0';}if(m)(*x)=-(*x);} void reader(int *x, int *y){reader(x);reader(y);} void reader(int *x, int *y, int *z){reader(x);reader(y);reader(z);} void reader(ll *x){int k,m=0;*x=0;for(;;){mygc(k);if(k=='-'){m=1;break;}if('0'<=k&&k<='9'){*x=k-'0';break;}}for(;;){mygc(k);if(k<'0'||k>'9')break;*x=(*x)*10+k-'0';}if(m)(*x)=-(*x);} int reader(char c[]){int i,s=0;for(;;){mygc(i);if(i!=' '&&i!='\n'&&i!='\r'&&i!='\t'&&i!=EOF) break;}c[s++]=i;for(;;){mygc(i);if(i==' '||i=='\n'||i=='\r'||i=='\t'||i==EOF) break;c[s++]=i;}return s;} void writer(int x, char c){int s=0,m=0;char f[10];if(x<0)m=1,x=-x;while(x)f[s++]=x%10,x/=10;if(!s)f[s++]=0;if(m)mypc('-');while(s--)mypc(f[s]+'0');mypc(c);} void writer(ll x, char c){int s=0,m=0;char f[20];if(x<0)m=1,x=-x;while(x)f[s++]=x%10,x/=10;if(!s)f[s++]=0;if(m)mypc('-');while(s--)mypc(f[s]+'0');mypc(c);} void writer(const char c[]){int i;for(i=0;c[i]!='\0';i++)mypc(c[i]);} void extended_euclid(ll x,ll y,ll *c,ll *a,ll *b){ ll a0,a1,a2,b0,b1,b2,r0,r1,r2,q; r0=x; r1=y; a0=1; a1=0; b0=0; b1=1; while(r1>0){ q=r0/r1; r2=r0%r1; a2=a0-q*a1; b2=b0-q*b1; r0=r1; r1=r2; a0=a1; a1=a2; b0=b1; b1=b2; } *c=r0; *a=a0; *b=b0; } ll get_inv(ll n, ll p){ ll a,b,c; extended_euclid(n,p,&c,&a,&b); if(a