#includecstdio#includecmath#includecstdlibusing namespace std;templatetypename Tinline void readT&x x=0; char s=getchar; bool f=false; while!s=0&&s=9 ifs==- f=true; s=getchar; whiles=0&&s=9 x=

#include #include #include using namespace std; const int N=1e3+10;

struct node { int x, y, w; };

int numOfWeights; double ans, ansX, ansY; node weights[N];

// Read template template inline void read(T&x) { x=0; char s=getchar(); bool f=false; while(!(s>='0'&&s<='9')) { if(s=='-') f=true; s=getchar(); } while(s>='0'&&s<='9') { x=(x<<1)+(x<<3)+s-'0'; s=getchar(); } if(f) x=(~x)+1; return; }

// Calculate potential energy double calculatePotentialEnergy(double x, double y) { double energy=0.0; for(int i=1; i<=numOfWeights; i++) energy+=sqrt((x-weights[i].x)(x-weights[i].x)+(y-weights[i].y)(y-weights[i].y))*weights[i].w; return energy; }

// Solve using simulated annealing algorithm void solve() { // Set initial temperature and cooling factor double temperature = 1e5; double coolingFactor = 0.996;

while(temperature > 1e-18)
{
	// Generate a random move
	double tmpX = ansX + (rand() + rand() - RAND_MAX) * temperature;
	double tmpY = ansY + (rand() + rand() - RAND_MAX) * temperature;
	
	// Calculate potential energy of the new move
	double tmpEnergy = calculatePotentialEnergy(tmpX, tmpY);
	
	// Calculate the difference in energy
	double energyDifference = tmpEnergy - ans;
	
	// Accept the move if it improves the solution or with a certain probability
	if(energyDifference < 0.0 || exp(-energyDifference / temperature) * RAND_MAX > rand())
	{
		ans = tmpEnergy;
		ansX = tmpX;
		ansY = tmpY;
	}
	
	// Cool down the temperature
	temperature *= coolingFactor;
}

}

int main() { srand(rand());

// Read the number of weights and their coordinates and weights
read(numOfWeights);
for(int i=1; i<=numOfWeights; i++)
{
	read(weights[i].x);
	read(weights[i].y);
	read(weights[i].w);
	ansX += weights[i].x;
	ansY += weights[i].y;
}

// Calculate the initial average position and potential energy
ansX /= numOfWeights;
ansY /= numOfWeights;
ans = calculatePotentialEnergy(ansX, ansY);

// Perform the solve function multiple times to improve the solution
for(int i=1; i<=4; i++)
	solve();

// Print the final average position
printf("%.3lf %.3lf\n", ansX, ansY);

return 0;