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package divideAndConquer;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;
public class Test {
public static double calculateGravitationalForce(double x, double m1,
double m2, double d) {
double G = 6.67e-11;
return G * m1 * m2 / Math.pow((d - x), 2);
}
public static double sumForcesFromLeft(double x, List<Double> xList,
List<Double> mList) {
int n = xList.size();
double fSum = 0;
for (int i = 0; i < n; i++) {
if (xList.get(i) < x) {
fSum += calculateGravitationalForce(x, mList.get(i), 1,
xList.get(i));
}
}
return fSum;
}
public static double sumForcesFromRight(double x, List<Double> xList,
List<Double> mList) {
int n = xList.size();
double fSum = 0;
for (int i = 0; i < n; i++) {
if (xList.get(i) > x) {
fSum += calculateGravitationalForce(x, mList.get(i), 1,
xList.get(i));
}
}
return fSum;
}
public static List<Double> findBalance(List<Double> xList,
List<Double> mList) {
int n = xList.size();
List<Double> balancePoints = new ArrayList<>();
for (int i = 0; i < n - 1; i++) {
double a = xList.get(i);
double b = xList.get(i + 1);
double tol = 1e-9;
int maxIter = 100;
int iter = 0;
while (Math.abs(a - b) > tol && iter < maxIter) {
double c = (a + b) / 2;
if (sumForcesFromLeft(c, xList, mList) == sumForcesFromRight(c,
xList, mList)) {
break;
} else if (sumForcesFromLeft(c, xList, mList) > sumForcesFromRight(
c, xList, mList)) {
a = c;
} else {
b = c;
}
iter++;
}
balancePoints.add((a + b) / 2);
}
return balancePoints;
}
public static void main(String[] args) throws FileNotFoundException {
System.setIn(new FileInputStream("Text"));
Scanner sc = new Scanner(System.in);
for (int i = 1; i <= 10; i++) {
// Read the number of magnetic materials
int n = sc.nextInt();
double[] x = new double[n];
double[] m = new double[n];
List<Double> xList1 = new ArrayList<>();
List<Double> mList1 = new ArrayList<>();
for (int j = 0; j < n; j++) {
x[j] = sc.nextDouble();
xList1.add(x[j]);
}
for (int j = 0; j < n; j++) {
m[j] = sc.nextDouble();
mList1.add(m[j]);
}
List<Double> balancePoints1 = findBalance(xList1, mList1);
System.out.print("#1 ");
for (Double point : balancePoints1) {
System.out.printf("%.10f ", point);
}
System.out.println();
}
sc.close();
}
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