'K' number of char arrays of different length are given, find Cartesian product of them in optimal way & give complexity.

Source : commented by user yen 

Given n, output the numbers from 0 to 2^n-1 (inclusive) in n-bit binary form, in such an order that adjacent numbers in the list differ by exactly 1 bit.

Source : Heard from Rahul, CSE, BITS ,2K10

Find the largest contiguous rectangle having all 1's in matrix of size m*n ; Matrix have only 0 and 1 .

Find the sum of all the multiples of 3 or 5 below 1 billion.

Since i dont want to stop hacking , i decided to post simple problem to start off the new year , Happy hacking , give its try !!!

PS: 1 billion is big no. its equal to no. of user facebook have ;)

Count maximum number of "connected 1" in given matrix

you have a matrix of N x N filled with 1 or 0. you can move only 1 step either right or 1 step down. you need to count maximum number of "connected 1" in given matrix. for example
0 0 1 1
1 1 1 0
1 0 1 0
0 1 0 1

[Start from top left] maximum no. of 1 is 4
[1,0][1,1][1,2][2,2]


Source -: Commented by a user "rakesh"

Find the minimal required number of white balls to achieve below criteria

You are given C containers, B black balls and an unlimited number of white balls. You want to distribute balls between the containers in a way that every container contains at least one ball and the probability of selecting a white ball is greater or equal to P percent. The selection is done by randomly picking a container followed by randomly picking a ball from it.

Find the color of the k-th ball (1-index based) that will be destroyed.

Bob is playing with his ball destroyer robot. Initially, Bob has r red balls, g green balls and b blue balls. The robot will repeat the following 3-step program until there are no balls left: If there is at least one red ball available, destroy one red ball. If there is at least one green ball available, destroy one green ball. If there is at least one blue ball available, destroy one blue ball. You are given the longs r, g and b. You are also given a long k. Find the color of the k-th ball (1-index based) that will be destroyed. If the color of the k-th ball to be destroyed is red, return "RED" (quotes for clarity, returned values are case-sensitive). If the color is green, return "GREEN". If the color is blue, return "BLUE". Source : Commented by a user named bob , later i found property of TopCoder , so i have am just sharing it to learning purpose , TopCoder Inc. holds all right on the problem statement .

Given an NxN matrix with unique integers : Find and print positions of all numbers such that it is the biggest in its row and also the smallest in its collumn .

Example

1 2 3
4 5 6
7 8 9


#A reader posted as comment .

Determine whether a number is colorful or not. 263 is a colorful number because (2,6,3,2x6,6x3,2x3x6) are all different whereas 236 is not because (2,3,6,2x3,3x6,2x3x6) have 6 twice. So take all consecutive subsets of digits, take their product and ensure all the products are different

#A reader posted in Comment

Given an array of strings ... find the string which is composed of other strings in the array and is of maximum size. Ex: ["satcatratbat" , "rat", "bat", "cat", "sat", "ratbat", "ratsatcat"]. Output: "satcatratbat"

Source: http://www.quora.com/Shashank-Mani-Narayan/Cracking-The-Code/String-matching-porblem