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#include <bits/stdc++.h>
using namespace std;
/// a * x + b * y = cmmdc(a,b)
int cmmdc(int a,int b,int &x,int &y){
if(b==0){
x=1;y=0;
return a;
}
int x1,y1;
int d=cmmdc(b,a%b,x1,y1);
x=y1;
y=x1-a/b*y1;
return d;
}
int InvMod(int A,int N){
/// cmmdc(A,N) = 1
/// A * x + N * y = 1
int inv,trash;
cmmdc(A,N,inv,trash);
if(inv<0) inv=inv-N*(inv/N-1);
else inv=inv%N;
return inv;
}
int main(){
freopen("inversmodular.in","r",stdin);
freopen("inversmodular.out","w",stdout);
int A,N;
cin>>A>>N;
cout<<InvMod(A,N);
}