Instructions
Objective
Write a java assignment to solve three identical points problem in java.
Requirements and Specifications
Project Overview
Three Identical Points
You may not use any data structures other than arrays to solve this problem.
You are given an nn-by-2, two-dimensional array which represents a list of nn points on the plane. For example, this array:
represents a list of 10 points with (xx,yy) coordinates of (3, 5), (20, -8), (9, 13), . . ., (3, 17).
Using a brute-force approach, write the method
public static int [] threeIdenticalPoints(int n, int [][] pts)
which takes an nn-by-2, two-dimensional array pts, where pts[i] is the array {x, y} giving the coordinates (xx, yy) of the iith point.
The method determines if (at least) three of the points in the list are identical (meaning all three points have the same xx and the same yy coordinates). If this is the case, return an array of size 3 of the form {i, j, k}, where the points in rows ii, jj, and kk are identical. If this is not the case, return the array {-1, -1, -1}.
Source Code
public class App
{
public static void main(String[] args)
{
int[][] pts = {
{3, 5},
{20, -8},
{9, 13},
{16, 17},
{20, 13},
{9, 13},
{3, 5},
{3, 40},
{9, 13},
{3, 17}
};
int[] result = threeIdenticalPoints(10, pts);
System.out.println(String.format("Three identical points found at {%d, %d, %d}", result[0], result[1], result[2]));
}
// Brute force method
public static int[] threeIdenticalPoints(int n, int[][] pts)
{
// Define the array that will store the index of the points
// Define it to have by default, values of -1
int[] result = {-1, -1, -1};
// Iterathe through the points
for(int i = 0; i < n-2; i++)
{
int[] point_i = pts[i];
// Now iterate from point i+1 to N-1
for(int j = i+1; j < n-1; j++)
{
int[] point_j = pts[j];
// Now, iterate from point j+1 to N
for(int k = j+1; k < n; k++)
{
int[] point_k = pts[k];
// check if the three points are equal
if(point_i[0] == point_j[0] && point_j[0] == point_k[0] && point_i[1] == point_j[1] && point_j[1] == point_k[1]) // the three points are equal
return new int[] {i, j, k};
}
}
}
return result;
}
}