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#include <iostream>
#include <fstream>
#include <vector>
#include <bitset>
#include <algorithm>
#include <cstring>
#include <cctype>
#define pb push_back
#define mp make_pair
#define MAXN 500001
#define DIM 8192
using namespace std;
class Reader
{
public:
Reader(const char* filename)
{
f.open(filename);
pos = 0;
f.read(buffer,DIM);
}
inline Reader& operator >>(int& x)
{
x=0;
sgn=1;
while((buffer[pos]<'0'||buffer[pos]>'9')&&buffer[pos]!='-')
if(++pos==DIM)
f.read(buffer,DIM),pos=0;
if(buffer[pos]=='-')sgn=-1,pos++;
while(buffer[pos]>='0'&&buffer[pos]<='9')
{
x=x*10+buffer[pos]-'0';
if(++pos==DIM)f.read(buffer,DIM),pos=0;
}
x*=sgn;
return (*this);
}
inline Reader& operator >>(char* c)
{
aux = 0;
while(isspace(buffer[pos]))
if(++pos==DIM)
f.read(buffer,DIM),pos=0;
while(!isspace(buffer[pos]))
{
c[aux++]=buffer[pos];
if(++pos==DIM)f.read(buffer,DIM),pos=0;
}
return (*this);
}
~Reader()
{
f.close();
}
private:
ifstream f;
int pos,aux,sgn;
char buffer[DIM];
};
class Writer
{
public:
Writer(const char* filename)
{
g.open(filename);
pos = 0;
}
inline Writer& operator <<(int xx)
{
aux = 0;
x = xx;
if(xx<0)x=-x;
if(x==0)
nr[aux++]='0';
while(x)
{
nr[aux++]=x%10+'0';
x/=10;
}
if(xx<0)nr[aux++]='-';
while(aux>0)
{
buffer[pos++]=nr[--aux];
if(pos==DIM)g.write(buffer,DIM),pos=0;
}
return (*this);
}
inline Writer& operator <<(const char* c)
{
aux = 0;
while(c[aux])
{
buffer[pos++]=c[aux++];
if(pos==DIM)g.write(buffer,DIM),pos=0;
}
return (*this);
}
~Writer()
{
g.write(buffer,pos);
g.close();
}
private:
ofstream g;
int pos,aux,x;
char buffer[DIM],nr[21];
};
Reader f("inversmodular.in");
Writer g("inversmodular.out");
int a,n,x,y;
void gcd(int a, int b, int& x, int& y)
{
if(b==0)
{
x=1;
y=0;
return;
}
int x0,y0;
gcd(b,a%b,x0,y0);
x=y0;
y=x0-(a/b)*y0;
}
int main()
{
ios_base::sync_with_stdio(false);
f>>a>>n;
gcd(a,n,x,y);
while(x<0)x+=n;
g<<x;
return 0;
}