=。= 之前做过有关果蝇算法的东西,然后发现这俩个其实就是一个东西。。。当时都没想啊,其实想到都不一定能撸对。
#include <cstdio> #include <cstring> #include <algorithm> #include <climits> #include <string> #include <iostream> #include <map> #include <cstdlib> #include <list> #include <set> #include <queue> #include <stack> #include<math.h> using namespace std; #define eps 1e-9 double a, b, c, d, e, f, z1, z2; const int dx[] = { 0, 0, 1, -1, 1, -1, 1, -1 }; const int dy[] = { 1, -1, 0, 0, -1, 1, 1, -1 }; int solvez(double x,double y) { double A = c , B = e * x + d * y, C = a * x * x + b * y * y + f * x * y - 1; double dlt = B * B - 4 * A * C; if (dlt < 0) return 0; z1 = (-B + sqrt(dlt)) / 2 / A, z2 = (-B - sqrt(dlt)) / 2 / A; if(z1 * z1 > z2 * z2) swap(z1, z2); return 1; } double dist(double x, double y, double z) { return sqrt(x * x + y * y + z * z) ; } void gao(double x,double y) { double Rand = 1.0; int flag = solvez(x , y); double Min = z1; while(Rand > eps) { double x1 = x ; double y1 = y; for(int i = 0; i < 8; i++) { double xx = x1 + dx[i] * Rand; double yy = y1 + dy[i] * Rand; if(!solvez(xx , yy)) continue; double dis = dist(xx, yy, z1); if(dis < Min) Min = dis, x = xx, y = yy; } Rand *= 0.99; } printf("%f ",Min); } int main() { while(cin >> a >> b >> c >> d >> e >> f){ gao(0, 0); } return 0; }