A centered hexagonal number is a centered figurate number that represents a hexagon with a dot in the center and all other dots surrounding the center dot in a hexagonal lattice.
Illustration of initial terms:
.
. o o o o
. o o o o o o o o
...
How to rotate the sequence S starting from ith element to jth element. In
other words, the ith element swaps its position with that of the jth element, (i+1)th
element swaps its position with that of the (j − 1)th element, and so on in O(log n) time, using augmented red black tree.
You place a standard die at the origin of a 2D grid that stretches infinitely in every direction. You place the die such that the 1 is facing upwards, the 2 is facing in the negative y direction, and the 3 is facing in the positive x direction, as shown in the figure below:
You then proceed to e...
Palindrome distance
Find what is the distance for a given string to its closest palindrome of the same length.
For this task I decided to give the characters further away from the string's center more weight (think of it as contributing more torque), proportional to their distance to the center.
...
Background
There is an interesting question on MathSE about some conjectures that are disproven by extremely large counter-examples. This delightful answer tells the story of a sequence of numbers called Gijswijt's sequence, which is now registered as A090822. The sequence is defined as follows
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I am trying to solve the City Tour problem from InterviewBit. I am getting wrong answer for the below input.
This is my solution below:
#define M 1000000007
void computerFactorial(long long *fact, int n)
{
fact[0] = 1; fact[1] = 1;
for(int i = 2; i <= n; i++)
{
fact[i] ...
Jelly, 8 bytes
”*x³s⁵j⁷
Try it online!
How it works
”*x³s⁵j⁷ Main link. No arguments.
”* Yield '*'.
x³ Repeat the character 100 times.
s⁵ Split into chunks of length 10.
j⁷ Join, separating by linefeeds.
Jelly, 7 bytes
”*x⁵Ṅ9¡
What's going on?
”*x⁵Ṅ9¡ - No arguments
”* - character literal, *
x - multiply (dyadic operation)
⁵ - integer literal, 10 (we have now constructed the string '**********')
Ṅ - Print & linefeed (monadic operation)
9 - integer literal, 9...
