/* program which takes the coordinates of two rectangles, and outputs TRUE if the squares overlap For example: with input as 0,0,4,4,1,1,7,7 --- the ouput is TRUE. */ public class OverlapTest { private class Point { int x; int y; } private class Rectangle { Point start; Point end; } public boolean checkSquareOverlap(String r1, String r2) { Rectangle leftRectangle = new Rectangle(); Rectangle rightRectangle = new Rectangle(); String [] r1Coordinates = r1.split(" "); String [] r2Coordinates = r2.split(" "); Point [] p = new Point[4]; for(int i =0 ; i <4 ; i++) p[i] = new Point(); p[0].x = Integer.valueOf(r1Coordinates[0]); p[0].y = Integer.valueOf(r1Coordinates[1]); p[1].x = Integer.valueOf(r1Coordinates[2]); p[1].y = Integer.valueOf(r1Coordinates[3]); p[2].x = Integer.valueOf(r2Coordinates[0]); p[2].y = Integer.valueOf(r2Coordinates[1]); p[3].x = Integer.valueOf(r2Coordinates[2]); p[3].y = Integer.valueOf(r2Coordinates[3]); if(p[0].x < p[2].x) { leftRectangle.start = p[0]; leftRectangle.end = p[1]; rightRectangle.start =p[2]; rightRectangle.end =p[3]; } else { leftRectangle.start = p[2]; leftRectangle.end = p[3]; rightRectangle.start =p[0]; rightRectangle.start =p[1]; } //check if they Overlap. if(rightRectangle.start.x > leftRectangle.start.x && rightRectangle.start.x < leftRectangle.end.x && rightRectangle.start.y > leftRectangle.start.y && rightRectangle.start.y < leftRectangle.end.y ) { //they overlap. return isSquarePresent(leftRectangle, rightRectangle); } else if(rightRectangle.start.x > leftRectangle.start.x && rightRectangle.start.x < leftRectangle.end.x && rightRectangle.end.y > leftRectangle.start.y && rightRectangle.end.y < leftRectangle.end.y ) { //they overlap. return isSquarePresent(leftRectangle, rightRectangle); } else { //they don't intersect and if they overlap they can't be //squares as rectangles are given as input. return false; } } private boolean isSquarePresent(Rectangle leftRectangle, Rectangle rightRectangle) { int l,b; l = leftRectangle.end.x - rightRectangle.start.x; b = leftRectangle.end.y - rightRectangle.start.y; return ( l == b); } public static void main(String [] args) { //Note: //The program only checks for square overlap in the Ist quadrant. String r1 = "0 0 4 4"; String r2 = "1 1 7 7"; OverlapTest t = new OverlapTest(); System.out.println("Overlap square condition met: " + t.checkSquareOverlap(r1,r2)); r1 = "0 0 8 8"; r2 = "4 4 9 9"; System.out.println("Overlap square condition met: " + t.checkSquareOverlap(r1,r2)); r1 = "0 0 8 8"; r2 = "3 4 9 9"; System.out.println("Overlap square condition met: " + t.checkSquareOverlap(r1,r2)); } }