#include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include using namespace std; typedef long long ll; #define sz size() #define pb push_back #define mp make_pair #define fi first #define se second #define all(c) (c).begin(), (c).end() #define rep(i,a,b) for(ll i=(a);i<(b);++i) #define per(i,a,b) for(ll i=b-1LL;i>=(a);--i) #define clr(a, b) memset((a), (b) ,sizeof(a)) #define ctos(c) string(1,c) #define print(x) cout<<#x<<" = "<>a>>b>>c; ll d = b*b-4*a*c; if(a==0&&b==0&&c==0){ cout << 0 << endl; } else if(a==0&&b==0){ cout << -1 << endl; } else if(a==0){ cout << 1 << endl; printf("%20.20f\n", -1.*c/b); } else if(d<0){ cout << 0 << endl; } else if(d==0){ cout << 1 << endl; printf("%20.20f\n", -1.*b/(2*a)); } else{ cout << 2 << endl; printf("%20.20f\n", (-1.*b-pow(d,0.5))/(2*a)); printf("%20.20f\n", (-1.*b+pow(d,0.5))/(2*a)); } return 0; }