#include #define all(v) v.begin(), v.end() #define rall(v) v.rbegin(), v.rend() #define rep(i,n) for(int i=0;i<(int)(n);i++) #define drep(i,j,n) for(int i=0;i<(int)(n-1);i++)for(int j=i+1;j<(int)(n);j++) #define trep(i,j,k,n) for(int i=0;i<(int)(n-2);i++)for(int j=i+1;j<(int)(n-1);j++)for(int k=j+1;k<(int)(n);k++) #define codefor int test;scanf("%d",&test);while(test--) #define INT(...) int __VA_ARGS__;in(__VA_ARGS__) #define LL(...) ll __VA_ARGS__;in(__VA_ARGS__) #define yes(ans) if(ans)printf("yes\n");else printf("no\n") #define Yes(ans) if(ans)printf("Yes\n");else printf("No\n") #define YES(ans) if(ans)printf("YES\n");else printf("NO\n") #define popcount(v) __builtin_popcountll(v) #define vector2d(type,name,h,...) vector>name(h,vector(__VA_ARGS__)) #define vector3d(type,name,h,w,...) vector>>name(h,vector>(w,vector(__VA_ARGS__))) #define vector4d(type,name,h,w,d,...) vector>>>name(h,vector>>(w,vector>(d,vector(__VA_ARGS__)))) using namespace std; using ll = long long; template using rpriority_queue = priority_queue, greater>; const int MOD=1000000007; const int MOD2=998244353; const int INF=1<<30; const ll INF2=1LL<<60; void scan(int& a){scanf("%d",&a);} void scan(long long& a){scanf("%lld",&a);} templatevoid scan(pair& p){scan(p.first);scan(p.second);} templatevoid scan(tuple& p){scan(get<0>(p));scan(get<1>(p));scan(get<2>(p));} template void scan(array& a){ for(auto&& i : a) scan(i);} template void scan(T& a){cin>>a;} template void scan(vector& vec){for(auto&& it:vec)scan(it);} void in(){} template void in(Head& head, Tail&... tail){scan(head);in(tail...);} void print(const int& a){printf("%d",a);} void print(const long long& a){printf("%lld",a);} void print(const double& a){printf("%.15lf",a);} templatevoid print(const pair& p){print(p.first);putchar(' ');print(p.second);} template void print(const T& a){cout< void print(const vector& vec){if(vec.empty())return;print(vec[0]);for(auto it=vec.begin();++it!= vec.end();){putchar(' ');print(*it);}} void out(){putchar('\n');} template void out(const T& t){print(t);putchar('\n');} template void out(const Head& head,const Tail&... tail){print(head);putchar(' ');out(tail...);} template void dprint(const T& a){cerr< void dprint(const vector& vec){if(vec.empty())return;cerr< void debug(const T& t){dprint(t);cerr< void debug(const Head& head, const Tail&... tail){dprint(head);cerr<<" ";debug(tail...);} ll intpow(ll a, ll b){ ll ans = 1; while(b){ if(b & 1) ans *= a; a *= a; b /= 2; } return ans; } ll modpow(ll a, ll b, ll p){ ll ans = 1; while(b){ if(b & 1) (ans *= a) %= p; (a *= a) %= p; b /= 2; } return ans; } ll modinv(ll a, ll m) {ll b = m, u = 1, v = 0;while (b) {ll t = a / b;a -= t * b; swap(a, b);u -= t * v; swap(u, v);}u %= m;if (u < 0) u += m;return u;} ll updivide(ll a,ll b){return (a+b-1)/b;} template void chmax(T &a,const T b){if(b>a)a=b;} template void chmin(T &a,const T b){if(b next_farey(pair a,ll N){ auto intermodinv=[&](ll a, ll m) { ll b = m, u = 1, v = 0; while (b) { ll t = a / b; a -= t * b; swap(a, b); u -= t * v; swap(u, v); } u %= m; if (u < 0) u += m; return u; }; pair ans; ll x, y, s; x = intermodinv(a.second, a.first); y = (a.second*x-1)/a.first; s = (N - y)/a.second; ans = {x+s*a.first, y+s*a.second}; return ans; } int main(){ LL(P,Q); auto R = next_farey({P,Q},Q); auto L = next_farey({Q-P,Q},Q); //out(L.first,L.second,R.first,R.second); L.first = L.second - L.first; /*while(R.second >= Q){ R = next_farey(R,Q); } while(L.first==0||L.second >= Q){ L = next_farey(L,Q); }*/ L={abs(L.first),L.second}; out(L.first+L.second+R.first+R.second); }