codewithyasar

Idea Behind BottomUp Approach:       In this approach,we find out the solution by divide into several sub problems and come up with a original solution from the small chunks.

Idea Behind Memoize technique: In the Recursion there are so many repetitive calls in that,in order to overcome that we need to declare an array to store the intermediate results and use that. Logic: Declare the Memo array and store the result and call them by position later. Code Logic: input to find fibonacci number at the position function declaration fib(n,memo) if memo[n]!=null:return memo[n] base condition n==1 or n==2 return 1 else return fib(n-1)+fib(n-2) Program:

Idea Behind Recursion:                Function call itself is called Recursion Like a binary tree it grows up to the end of the tree and start computation from the base case Logic: we need to define base case Then we set the recursive calls Code Logic: input the position we need to find fibonacci 'p' function for fibRecur() basecase if n==1 or n==2 return 1 else return fibRecur(n-1) +fibRecur(n-2) Program:

Explanation:          We can simply define what is the range, we need to find prime numbers in between.          Starting from min prime we need to eliminate the tables of min prime ..so on and so forth          Repeat for next number. By SKopp at German Wikipedia - Own work , Original image at Image:Animation_Sieve_of_Eratosth.gif , CC BY-SA 3.0 , Link Program: Output:              Enter upper limit of range: 10             {2, 3, 4, 5, 6, 7, 8, 9, 10}             2    3   5  7     

Haunted Hotel Follow the instructions to live 6th June 1906, there was a big fire accident at a 5 star hotel in which more than 160 people died, from that time no one even dared to go near that burnt place, because it was believed that the place became haunted. This fear among people went increasing due to the suspicious deaths of the people who tried entering the hotel. More than 100 years have passed, but that has not reduced thee fear among the people even a bit. Dhoni is a person who likes adventures, so wanted to see what actually is the mystery of the hotel. So on a Friday evening he went inside the hotel with a camera which was live streamed live on his Facebook page.   The live stream lasted not even for an hour, all the electronic equipment he had began malfunctioning. He might be brave, but being alone in a place which is believed to be haunted and that too in late evening, his nerves got him. It was so quite so that, he could hear his own heart beat increasing as a d...

Mountain Peak Sequence Consider the first three natural numbers 1, 2, 3. These can be arranged in the following ways: 2, 3, 1 and 1, 3, 2. Inboth of these arrangements, the numbers increase to a certain point and then decrease. A sequence with this property is called a “mountain peak sequence”. Given an integer N, write a program to find the remainder of mountain peak arrangements that can be obtained by rearranging the numbers 1, 2, …, N. Input Format : One line containing the integer N Input Constraints : Mod = 10^9 +7 3 ≤ N ≤ 10^9 Output Format : An integer m, giving the remainder of the number of mountain peak arrangements that could be obtained from 1, 2, …, N is divide by Mod Sample Input : 3 Sample Output : 2 Explanation:      If mountain like sequence are formed using the number then count it. Understand the logic: For input 3, 6 combinations can be formed,out of these 2 is a mountain sequence. For input 4, 24 combinations can be formed,out of th...

Even Sum A number is even if it is divisible by 2, but in this case a number is even if the active bits (1s in its binary representation) of a given number are 2. So your task is to find the sum of first N even numbers. Input Format : The first line of the input contains an integer T denoting the number of test cases Each of the next T lines contains a single integer N. Input Constraints : 0 < N <=10^5 Output Format : For each test case, print a single integer denoting sum of first N even numbers mod 1000000007. Sample Input : 2 15 20 Sample Output : 315 666 Explanation of Question: They are asking for sum of even numbers but here the even numbers are those having even number of active bits Active bits are nothing but one. Logic:         Active even bits come in the format like            3,5,6,9,10,12,17,18,20,24...             There are two patterns we find ou...