#pragma GCC optimize("Ofast") #include #include #include #include #include #include #include #include #include const long long INF_L = 1e17+7; const long long INF_I = 1e9+7; const long long MOD = 1e9+7; const double EPS = 1e-8; const double PI=acos(-1); using namespace std; long long GCD(long long a,long long b){ long long x=max(a,b),y=min(a,b); if(x%y==0){ return y; }else{ return GCD(y,x%y); } } bool sqr_2bun(long long x){ long long start=0; long long end=x*2; int id=0; long long mid; if(x==1){ return true; } while(1){ mid=(end+start)/2; if(end-start<=1){ if(end*end==x || start*start==x){ return true; }else{ return false; } } if(mid*mid>x){ end=mid; }else if(mid*mid> a >> b; long long g=GCD(a,b); if(sqr_2bun(g)){ cout << "Odd" << endl; }else{ cout << "Even" << endl; } return 0; }