I found out valuable facts about world famous android OS

android-icon

From Rahul

1). It wasn’t Google’s idea: Android was the brainchild of Andy Rubin, who founded Android Inc. in October 2003 with the aim of creating a new mobile platform. Google later bought Android Inc. and hired Rubin and others in August 2005.

Andy Rubin
Andy Rubin

2). It almost didn’t work out: Android almost immediately ran out of cash after its founding, only to be saved, according to the Businessweek, by Steve Perlman.

Steve Perlman

3). The Nexus line was a hot rumour years before the Nexus One: People started predicting about the “gPhone” as early as 2007 though Nexus came out in 2010.

gPhone

4). Microsoft thought it would be a non-event: Microsoft’s Scott Horn, then head of the Windows Mobile marketing team, had told Engadget after Android’s release, “I don’t understand the impact they are going to have.”

Scott Horn
( A Former head of the Windows Mobile marketing team)

5). Resolution scaling was introduced in Version 1.6: The ability to automatically scale images based on display size appeared in Donut, or Android 1.6, paving the way for the huge range of device form factors on the Android market today.

Donut – Android 1.6

6). There’s an Android phone in space: A British firm launched a Nexus phone on Space, to control a satellite as part of an experiment and see how well consumer-grade electronics stand up to the rigors of space.

NASA sends another cheap Android-powered satellite in space, makes it dial home

 

7). Every app you run on your Android phone gets its own virtual machine: Each active app on an Android device runs in its own Dalvik VM, which keeps it safe and separate from core functions. This improves battery life and boosts performance of the phone.

The Android OS stack and Dalvik VM

 

The first official version code name was NOT a dessert: Google’s Dan Morrill confirmed in January that the very first alpha version of Android released to internal developers was R2-D2.

r2-d2

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Simple PHP Code show, How many Days Remain to Holiday

<?php 
$target = mktime(0, 0, 0, 12, 25, 2014);
 //within above bracket you need give (0, 0, 0, Month, Date, Year )
$today = time() ;
$difference =($target-$today) ;
$days =(int) ($difference/86400) ;
print "Holiday is in $days days";
?>

This PHP code automatically count and illustrate how many Days remain to your holiday

click this link to view online how this code works http://codepad.org/Je3RTysF

Hash Table with Linear Probing

Question:

Consider a hash table with m slots that uses open addressing with linear probing. The table is initially empty. A key k1 is inserted into the table, followed bykey k2, and then key k3. What is the probability that the total number of probes while inserting these keys is at least 4?

1. if 1st 2 keys collide

2. if 1st 2 keys don’t collide  ,1st key and 3rd key collide

3. if 1st 2 keys don’t collide  , 2nd  key and 3rd key collide

 

Since the insertion of each element requires at least one(Its only one on this term) probe, for there to be 4 probes, there needs to be at least one collision.

If the first two keys collide, we do not even need to know where the third key hashes to – there is already a collision. The probability that the first two keys collide is 1/m.

If the first two keys do not collide, then the third key needs to hash to one of the two slots that the first two keys hash to in order for there to be a collision. The probability of this happening is the product of the probability that the first two keys do not collide and the probability that the third key goes into one of the two slots that the first two keys hash to: (m-1)/m *2/m

The total probability of having at least 4 probes is
1/m + (m-1)/m *2/m

RESOURCE : MIT Handout