# Self-hatred

## Project Euler Problem #11

I took a pure brute force approach to this problem: Working with [x,y] coordinates is a headache. I also chose to go the route of testing every valid combination; way, way too many submissions on the Project Euler forums (and on the Internet in general) are along the lines of “I just did Ctrl+F for 99, and visually inspected the grid for the highest sequence!”

Yeah, that’s great; while it’s fast, and a testament to your ability to recognize patterns, you aren’t comprehensively solving the problem in a rigorous, repeatable fashion.

All of the above said, this problem was…eh. There was nothing cool going on here. Some hard thought about how to parse input before I said “fuck it” and just plugged everything into a pre-parsed grid.

```using System;

public class Eleven
{
static void Main()
{
int[][] a = new int[20][];
int     b = 0;
int     c = 0;

a[0]  = new int[20] {08,02,22,97,38,15,00,40,00,75,04,05,07,78,52,12,50,77,91,08};
a[1]  = new int[20] {49,49,99,40,17,81,18,57,60,87,17,40,98,43,69,48,04,56,62,00};
a[2]  = new int[20] {81,49,31,73,55,79,14,29,93,71,40,67,53,88,30,03,49,13,36,65};
a[3]  = new int[20] {52,70,95,23,04,60,11,42,69,24,68,56,01,32,56,71,37,02,36,91};
a[4]  = new int[20] {22,31,16,71,51,67,63,89,41,92,36,54,22,40,40,28,66,33,13,80};
a[5]  = new int[20] {24,47,32,60,99,03,45,02,44,75,33,53,78,36,84,20,35,17,12,50};
a[6]  = new int[20] {32,98,81,28,64,23,67,10,26,38,40,67,59,54,70,66,18,38,64,70};
a[7]  = new int[20] {67,26,20,68,02,62,12,20,95,63,94,39,63,08,40,91,66,49,94,21};
a[8]  = new int[20] {24,55,58,05,66,73,99,26,97,17,78,78,96,83,14,88,34,89,63,72};
a[9]  = new int[20] {21,36,23,09,75,00,76,44,20,45,35,14,00,61,33,97,34,31,33,95};
a[10] = new int[20] {78,17,53,28,22,75,31,67,15,94,03,80,04,62,16,14,09,53,56,92};
a[11] = new int[20] {16,39,05,42,96,35,31,47,55,58,88,24,00,17,54,24,36,29,85,57};
a[12] = new int[20] {86,56,00,48,35,71,89,07,05,44,44,37,44,60,21,58,51,54,17,58};
a[13] = new int[20] {19,80,81,68,05,94,47,69,28,73,92,13,86,52,17,77,04,89,55,40};
a[14] = new int[20] {04,52,08,83,97,35,99,16,07,97,57,32,16,26,26,79,33,27,98,66};
a[15] = new int[20] {88,36,68,87,57,62,20,72,03,46,33,67,46,55,12,32,63,93,53,69};
a[16] = new int[20] {04,42,16,73,38,25,39,11,24,94,72,18,08,46,29,32,40,62,76,36};
a[17] = new int[20] {20,69,36,41,72,30,23,88,34,62,99,69,82,67,59,85,74,04,36,16};
a[18] = new int[20] {20,73,35,29,78,31,90,01,74,31,49,71,48,86,81,16,23,57,05,54};
a[19] = new int[20] {01,70,54,71,83,51,54,69,16,92,33,48,61,43,52,01,89,19,67,48};

// Just for clarity:
//  i is always down.
//  j is always across.

// Across.
for (int i = 0; i < 20; i++)
for (int j = 3; j < 20; j++)
{
b = a[i][j] * a[i][j - 1] * a[i][j - 2] * a[i][j - 3];

if (b > c)
c = b;
}

// Down.
for (int i = 3; i < 20; i++)
for (int j = 0; j < 20; j++)
{
b = a[i][j] * a[i-1][j] * a[i-2][j] * a[i-3][j];

if (b > c)
c = b;
}

// Left Diagonal.
for (int i = 3; i < 20; i++)
for (int j = 3; j < 20; j++)
{
b = a[i][j] * a[i-1][j-1] * a[i-2][j-2] * a[i-3][j-3];

if (b > c)
c = b;
}

// Right Diagonal.
for (int i = 3; i < 20; i++)
for (int j = 0; j < 17; j++)
{
b = a[i][j] * a[i-1][j+1] * a[i-2][j+2] * a[i-3][j+3];

if (b > c)
c = b;
}

Console.WriteLine("\n{0}\n", c);
}

}```

Categorised as: programming