RSA has this app for iPhone to generate keys that is needed to login to corporate VPNs enabled through RSA. Installing it is easy. But, getting the key into it is not very straightforward. Well, No more… because you folks have this tutorial

Install the RSA app (linked above) into iPhone and get your RSA login key .sdtid file before doing the instructions below…

1. Download the RSA’s TokenConverter tool (It will ask you for a valid email id and accept license agreement terms)
2. Open your command prompt and run the following command from the folder where you have extracted TokenConverter tool
   TokenConverter <.sdtid file path> -mobile -p <password if any>
   some corporations will create your .sdtid file with a unique password. Type it in if you got your .sdtid file with a password 
3. The above command when executed successfully should print a generated ctf string in the console. Copy it. It will look something like
   com.rsa.securid://ctf?ctfData=2000119722625607285525965262252517630605010534242616025667355410
4. Compose a mail with a hyperlink pointing to the above copied url and send it to an account accessible from your iPhone. Sample:
   <a href=”com.rsa.securid://ctf?ctfData=2000119722625607285525965262252517630605010534242616025667355410″> Click here to install the key</a>
5. Open this mail in your iPhone and click on the link to automatically load RSA SecurID application. It will start installing the token.
6. Goyala!!! It is done! You should be able to generate login tokens on the move from now.

Note: I tried by best to add all the possible festivals into it (as far as I could google). So, Beware and don’t hold me responsible for your god’s fury!

The following instructions will help you to make it happen. What we are trying to do is connecting a router to another router…

Wi5 WLAN Router:

1. Make sure you are able to connect to the internet directly without your router in the picture
2. Open the Wi5 router’s admin page (192.168.1.254 by default)
3. Go to the LAN Interface under TCP/IP settings and make sure DHCP server is set in server mode
4. Updated DHCP client range wide enough based on how many devices you want to connect to your home router

Home Wireless Router:

Almost all the routers will have atleast 4 LAN ports to connect other devices to the network and a separate LAN port for connecting the ISP’s modem. Since Wi5 does not actually have a separate modem but instead is a modem+router, how you connect the both is bit different…

1. Connect the Wi5 router to your home router in one of the 4 LAN sockets
2. Login to your home router and disable its DHCP server. There can be only one DHCP server in a network and since we have enabled Wi5 router’s DHCP server, this is not needed.
3. Restart the router if needed/prompted

This should do.

“I have a mathematical expression say (45 + ((4 – 25) + 2)) as a string. How can you evaluate it to find the result using JAVA programming language?”

Well, this is very easy with javascript as it has the powerful eval() function. But java is static, strongly typed, not-that-fexible language. So, this cannot be provided as a language feature which leads me to either search for some available libraries or, write my won little library. If you are reading this post, you know by now what my decision was:) Come on, what’s fun in searching for someone’s work (Well, not always)

So, here it is… This would have been much simpler with dynamic language like Groovy… But, the requirement clearly said JAVA

Logic is quite simple. The given input is an infix expression. Use stack and keep pushing all the elements (including braces) till you encounter a closed brace. Now, popping from the stack till you encounter an open brace will get you an operator and 2 operands. Evaluate it and push back the result to continue the same logic till the end of the input string.

 package com.rs.utils;

 import java.util.ArrayList;
 import java.util.Stack;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;

 public class Evaluator {

 	public static int eval(String infixExpression) {
 		Stack<String> stack = new Stack<String>();
 		String trimmedExp = infixExpression.replaceAll(" ", "");
 		for (String c : split(trimmedExp)) {
 			if (")".equals(c)) {
 				if (!"(".equals(stack.peek())) {
 					String result = performOperation(stack.pop(), stack.pop(),
 							stack.pop()) + "";
 					stack.pop(); // remove also the open bracket
 					stack.push(result);
 				}
 			} else {
 				stack.push(c);
 			}
 		}
 		return Integer.parseInt(stack.pop());
 	}

 	private static int performOperation(String operand2, String operator,
 			String operand1) {
 		int op1 = Integer.parseInt(operand1);
 		int op2 = Integer.parseInt(operand2);
 		switch (operator.toCharArray()[0]) {
 			case '+': return op1 + op2;
 			case '-': return op1 - op2;
 			case '*': return op1 * op2;
 			case '/': return op1 / op2;
 			default: return 0;
 		}
 	}

 	static String[] split(String exp) {
 		ArrayList<String> parts = new ArrayList<String>();
 		Pattern pat = Pattern.compile("\\d++|\\+|\\-|\\*|/|\\(|\\)");
 		Matcher matcher = pat.matcher(exp);
 		while (matcher.find()) {
 			parts.add(matcher.group());
 		}
 		return parts.toArray(new String[0]);
 	}
 }

It actually plays all DivX, Xvid & VOB files. But fails to recognize mp4 videos. Well, you might ask why should I be concerned if it plays more than it mentions right? If I had known this before, I might not have ordered AppleTV. (Out of the box even it does not play all the formats but you can install Boxee into it)

I guess all the latest LG TVs does the same. Better check it in the store with a flash drive before buying… I got mine for 36,500Rs in Girias.

Configuration you need to set in “Mobile Partner”

Settings

To take backup of your iPhone…

Contacts : Use iTunes
SMS : Copy the sms.db in /private/var/mobile/Library/SMS to local and restore it back after upgrade*
Notes : Copy the notes.db in /private/var/mobile/Library/Notes to local and restore it back after upgrade*

* You should have installed OpenSSH in your iPhone through Cydia to remote login from a PC and copy these files

After reading what they are trying to say in that section, I realized they mean what plain english word means when you say “spring” and “strut”…

But, I felt this as a rare coincidence to see these words together in the least expected spot

Struts & Springs

Check out my implementation below… It did not look this small and simple when I started solving it. Tried calculating angles between edges, tried equating edge lengths, tried rotating the skewed rectangles (special case), tried getting B.Sc. Maths degree first… But, all of these are not really needed for the solution…  It is enough if you calculate the centroid and make sure all the 4 points are equi-distant from the centroid. Well, square also satisfies this logic and square is also a rectangle

I guess it is always hard to come up with a simple solution… You have to put lot of effort to think simple!

 public class RectangleValidator {

 	public static boolean validate(Point p1, Point p2, Point p3, Point p4) {
 		// Find the centroid using Euclid's geometric principle
 		Point centroid = new Point();
 		centroid.x = (p1.x + p2.x + p3.x + p4.x) / 4;
 		centroid.y = (p1.y + p2.y + p3.y + p4.y) / 4;

 		// Now check if the centroid is equi-distant from all the corners
 		double dist1 = getLength(p1, centroid);
 		double dist2 = getLength(p2, centroid);
 		double dist3 = getLength(p3, centroid);
 		double dist4 = getLength(p4, centroid);
 		return (dist1 == dist2 && dist2 == dist3 && dist3 == dist4 && dist4 == dist1);
 	}

 	private static double getLength(Point p1, Point p2) {
 		// Using pythogoras theorem
 		double xDiff = Math.abs(p1.x - p2.x);
 		double yDiff = Math.abs(p1.y - p2.y);
 		return Math.sqrt((xDiff * xDiff) + (yDiff * yDiff));
 	}

 	public static class Point {
 		Point() {
 		}

 		Point(double x, double y) {
 			this.x = x;
 			this.y = y;
 		}

 		double x;
 		double y;
 	}

 }

Thanks to Code2HTML