#include <bits/stdc++.h> using namespace std; typedef signed long long ll; #undef _P #define _P(...) (void)printf(__VA_ARGS__) #define FOR(x,to) for(x=0;x<(to);x++) #define FORR(x,arr) for(auto& x:arr) #define FORR2(x,y,arr) for(auto& [x,y]:arr) #define ITR(x,c) for(__typeof(c.begin()) x=c.begin();x!=c.end();x++) #define ALL(a) (a.begin()),(a.end()) #define ZERO(a) memset(a,0,sizeof(a)) #define MINUS(a) memset(a,0xff,sizeof(a)) //------------------------------------------------------- ll A,B; void solve() { int i,j,k,l,r,x,y; string s; cin>>A>>B; A=abs(A); B=abs(B); if(A>B) swap(A,B); if(B==0) { cout<<0.25<<endl; return; } double ret=0; ll g=__gcd(A,B); int par=(A/g+B/g)%2; for(ll x=1;x<=1000;x+=g) { for(ll y=1;y<=1000;y+=g) { if(par==0 && ((x-1)/g+(y-1)/g)%2==1) continue; ret+=1.0/pow(x+y,x+y); } } _P("%.12lf\n",ret); } int main(int argc,char** argv){ string s;int i; if(argc==1) ios::sync_with_stdio(false), cin.tie(0); FOR(i,argc-1) s+=argv[i+1],s+='\n'; FOR(i,s.size()) ungetc(s[s.size()-1-i],stdin); cout.tie(0); solve(); return 0; }