#include #include #define MOD 1000000007 int main() { int a, b, c; scanf("%d %d %d", &a, &b, &c); if (a==0) { printf("-1\n"); return 0; } long long D=(b*b)%MOD-4*a*c; double f=(-b-sqrt(b*b-4.0*a*c))/2.0*a, s=(-b+sqrt(b*b-4.0*a*c))/2.0*a; if (D>0) { printf("2\n"); printf("%.16lf\n", f