Skip to content

feat: solution to project euler problem 11 #871

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
wants to merge 4 commits into
base: master
Choose a base branch
from
+121 −0
Open

feat: solution to project euler problem 11 #871

Changes from all commits
Commits
Show all changes
4 commits
Select commit Hold shift + click to select a range
cd5b949
Solution: project euler problem 11
Vipul-Cariappa Oct 7, 2021
db9a9e9
updates sol1.c
Vipul-Cariappa Oct 8, 2021
24341eb
updated sol1.c
Vipul-Cariappa Oct 8, 2021
55faf5e
Update project_euler/problem_11/sol1.c
Vipul-Cariappa Oct 9, 2021
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
121 changes: 121 additions & 0 deletions project_euler/problem_11/sol1.c
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,121 @@
/**
* @file
* @brief [Problem 11](https://projecteuler.net/problem=11) solution
* @author [Vipul Cariappa](https://github.com/vipul-cariappa)
* @details
* Code to find the greatest product of four adjacent numbers in the same
* direction (up, down, left, right, or diagonally) in the given grid
*/

#include <stdio.h> /// for IO operations

#define ARRAY_SIZE 20 // size of gird
typedef unsigned long long large; // To hold product of numbers

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

// to store present largest number
large biggest = 0;
large tmp;

for (int i = 0; i < ARRAY_SIZE; i++)
{
for (int j = 0; j < ARRAY_SIZE; j++)
{
// calculating product and checking against prest biggest number
// row
if (j < ARRAY_SIZE - 4)
{
tmp = (large)array[i][j] * array[i][j + 1] * array[i][j + 2] *
array[i][j + 3];
if (tmp > biggest)
{
biggest = tmp;
}
}

// column
if (i < ARRAY_SIZE - 4)
{
tmp = (large)array[i][j] * array[i + 1][j] * array[i + 2][j] *
array[i + 3][j];
if (tmp > biggest)
{
biggest = tmp;
}
}

// diagonal (towards down left)
if ((i < ARRAY_SIZE - 4) && (j < ARRAY_SIZE - 4))
{
tmp = (large)array[i][j] * array[i + 1][j + 1] *
array[i + 2][j + 2] * array[i + 3][j + 3];
if (tmp > biggest)
{
biggest = tmp;
}
}

// diagonal (towards down right)
if ((j > 3) && (i < ARRAY_SIZE - 4))
{
tmp = (large)array[i][j] * array[i + 1][j - 1] *
array[i + 2][j - 2] * array[i + 3][j - 3];
if (tmp > biggest)
{
biggest = tmp;
}
}
}
}

printf("Largest Product: %llu\n", biggest);
return 0;
}