Not really any mysterious about it, nor anything particularly interesting. Comments by Disqus. The Tonelli-Shanks algorithm can be used to solve the congruence:. Can you please help? Bet I spent less energy and time on making those numbers into an array, than you spent writing that input reader :p Why do you have two identical blogs with the same name anyways? I can confirm that the answer on both questions is indeed no. Please keep up posting. Name Email address:.

Greatest product in 20×20 grid – Problem In the 20*20 grid below, four numbers along a diagonal line have been marked in red. What is the greatest product of four adjacent numbers in any direction (up, down, left, right, or diagonally) in the 20*20 grid?.

Euler Problem 11 is a fairly straightforward application of vector arithmetics in R. Just like problem 8, it asks for the largest product.

## One solution to Project Euler problem 11 in java · GitHub

This is one of the earlier problems on the PE website but is very challenging and required the longest PE code I have ever written. It was also.

I can see where you are going with that, and it could be a better solution.

I promise I will include cool tidbits for you. Please keep up posting. Is there a difference in the optimal approach in C? Hint 2: Repeated Squaring Many Euler problems — and number-theoretic computations in general — are based on the following operation: compute a to the power of b modulo m.

08 02 22 97 38 15 00 40 00 75 04 05 07 78 52 12 50 If LIST were a two-dimensional numpy array, you could use LIST[i:] to get the i th row, LIST[:i] to get the i th column, al(LIST, i) to. Problem: In the grid below, four numbers along a diagonal line have been marked in red. 08 02 22 97 38 15 00 40 00 75 04 05 07 78 52 12

Sorry for appearing to ignore you. The Sieve of Eratosthenes just crosses out all numbers that are not prime.

I can confirm that the answer on both questions is indeed no.

## Project Euler problem9 solution in C++ Khuram Ali

Is there a difference in the optimal approach in C? If you find some optimized way of doing this, please let me know, I would be interested.

Going through the whole grid while checking every single possibility is. This problem is a programming version of Problem 11 from In the grid below, four numbers along a diagonal line have been marked in bold.

## Problem 11 Project Euler

(see =11). In the 20x20 grid below, four numbers along a diagonal line have been marked in red.

08 02 22 97 38 15

This forum is not meant to publish solutions. So for a root g it is sufficient to check if Because by multiplying with g you can induce all other triples as well: Hint 4: Quadratic Equations The potential solution s to quadratic equations in modular arithmetic are derived the same way as for regular algebra.

Line 8 has the same problem; but it has hXX,vXX combinations, so this is simpler. January 9, Why do you have 4 inner loops, instead of using one?

Accompanying the previous comment.

Nghia Luong. So basically you can copy the text from the web page.

I here I am thinking of Problem 8.

I was bit confused about how to find answer to this questions. So for instance, you would cross 49 as soon as you get to the prime 7.

This site uses cookies. Not really any mysterious about it, nor anything particularly interesting.