Permalink
Browse files

Solved 11

  • Loading branch information...
1 parent 01e1b96 commit 9361d7665cbfa21aedfbd44d04a0d18875398555 @ndbroadbent committed Oct 14, 2010
Showing with 203 additions and 0 deletions.
  1. +120 −0 11/solution.c
  2. +83 −0 11/solution.rb
View
@@ -0,0 +1,120 @@
+// Solving Project Euler Problem #11
+#include <iostream>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string>
+#include <math.h>
+using namespace std;
+
+void rotate_matrix(int matrix[20][20], int * n) {
+ int tmp;
+ for (int i=0; i<*n/2; i++){
+ for (int j=i; j<*n-i-1; j++){
+ tmp = matrix[i][j];
+ matrix[i][j] = matrix[j][*n-i-1];
+ matrix[j][*n-i-1]= matrix[*n-i-1][*n-j-1];
+ matrix[*n-i-1][*n-j-1]=matrix[*n-j-1][i];
+ matrix[*n-j-1][i]=tmp;
+ }
+ }
+}
+
+void find_max_horizontal_product(int matrix[20][20], int * n, long * max_product, int factors[4]) {
+ // Iterate over each row
+ for (int y=0; y < *n; y++){
+ // Iterate over the first til 4th from last columns
+ for (int x=0; x < *n - 4; x++){
+ long product = 1;
+ // Multiply the 4 neighboring indices together.
+ for (int i=0; i < 4; i++)
+ product *= matrix[x + i][y];
+ // Set max_product if it is greater.
+ if (product > *max_product){
+ *max_product = product;
+ cout << "===== Max product so far: (" << *max_product << ") -- factors = ";
+ for (int i=0; i < 4; i++){
+ factors[i] = matrix[x + i][y];
+ cout << factors[i];
+ if (i < 3)
+ cout << ", ";
+ }
+ cout << "\n";
+ }
+ }
+ }
+}
+
+void find_max_diagonal_product(int matrix[20][20], int * n, long * max_product, int factors[4]) {
+ // Iterate over the first til 4th from last rows
+ for (int y=0; y < *n; y++){
+ // Iterate over the first til 4th from last columns
+ for (int x=0; x < *n - 4; x++){
+ long product = 1;
+ // Multiply the 4 neighboring indices together.
+ for (int i=0; i < 4; i++)
+ product *= matrix[x + i][y + i];
+ // Set max_product if it is greater.
+ if (product > *max_product){
+ *max_product = product;
+ cout << "===== Max product so far: (" << *max_product << ") -- factors = ";
+ for (int i=0; i < 4; i++){
+ factors[i] = matrix[x + i][y];
+ cout << factors[i];
+ if (i < 3)
+ cout << ", ";
+ }
+ cout << "\n";
+ }
+ }
+ }
+}
+
+int main (int argc, char *argv[])
+{
+ int mSize = 20;
+ long max_product = 0;
+ int factors[4];
+ int matrix[20][20] = {
+ { 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}
+ };
+
+ for (int i=1; i<=4; i++){
+ cout << "== Processing rotation (" << i << ")...\n";
+ cout << "==== Horizontal products...\n";
+ find_max_horizontal_product(matrix, &mSize, &max_product, factors);
+ cout << "==== Diagonal products...\n";
+ find_max_diagonal_product(matrix, &mSize, &max_product, factors);
+
+ rotate_matrix(matrix, &mSize);
+ }
+
+ cout << "\n\n? Max product was: (" << max_product << ") -- factors = ";
+ for (int i=0; i < 4; i++){
+ cout << factors[i];
+ if (i < 3)
+ cout << ", ";
+ }
+ cout << "\n\n";
+
+ return(0);
+}
+
View
@@ -0,0 +1,83 @@
+#!/usr/bin/env ruby
+# coding: utf-8
+# -----------------------------------------
+# | A solution to a Project Euler problem |
+# -----------------------------------------
+require 'rubygems'
+require 'pp'
+require 'ap'
+problem_no = File.dirname(File.expand_path(__FILE__)).split('/').last
+puts "=== Solving Project Euler problem ##{problem_no}\n\n"
+question = %Q{
+
+In the 20×20 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 50 77 91 08
+49 49 99 40 17 81 18 57 60 87 17 40 98 43 69 48 04 56 62 00
+81 49 31 73 55 79 14 29 93 71 40 67 53 88 30 03 49 13 36 65
+52 70 95 23 04 60 11 42 69 24 68 56 01 32 56 71 37 02 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 03 45 02 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 02 62 12 20 95 63 94 39 63 08 40 91 66 49 94 21
+24 55 58 05 66 73 99 26 97 17 78 78 96 83 14 88 34 89 63 72
+21 36 23 09 75 00 76 44 20 45 35 14 00 61 33 97 34 31 33 95
+78 17 53 28 22 75 31 67 15 94 03 80 04 62 16 14 09 53 56 92
+16 39 05 42 96 35 31 47 55 58 88 24 00 17 54 24 36 29 85 57
+86 56 00 48 35 71 89 07 05 44 44 37 44 60 21 58 51 54 17 58
+19 80 81 68 05 94 47 69 28 73 92 13 86 52 17 77 04 89 55 40
+04 52 08 83 97 35 99 16 07 97 57 32 16 26 26 79 33 27 98 66
+88 36 68 87 57 62 20 72 03 46 33 67 46 55 12 32 63 93 53 69
+04 42 16 73 38 25 39 11 24 94 72 18 08 46 29 32 40 62 76 36
+20 69 36 41 72 30 23 88 34 62 99 69 82 67 59 85 74 04 36 16
+20 73 35 29 78 31 90 01 74 31 49 71 48 86 81 16 23 57 05 54
+01 70 54 71 83 51 54 69 16 92 33 48 61 43 52 01 89 19 67 48
+
+The product of these numbers is 26 × 63 × 78 × 14 = 1788696.
+
+What is the greatest product of four adjacent numbers in any direction (up, down, left, right, or diagonally) in the 20×20 grid?
+
+
+}
+puts "? #{question.strip}\n\n"
+# --------------------------------------------------------------------
+
+puts "==== Generated C++ Matrix..."
+
+matrix = %Q{
+08 02 22 97 38 15 00 40 00 75 04 05 07 78 52 12 50 77 91 08
+49 49 99 40 17 81 18 57 60 87 17 40 98 43 69 48 04 56 62 00
+81 49 31 73 55 79 14 29 93 71 40 67 53 88 30 03 49 13 36 65
+52 70 95 23 04 60 11 42 69 24 68 56 01 32 56 71 37 02 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 03 45 02 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 02 62 12 20 95 63 94 39 63 08 40 91 66 49 94 21
+24 55 58 05 66 73 99 26 97 17 78 78 96 83 14 88 34 89 63 72
+21 36 23 09 75 00 76 44 20 45 35 14 00 61 33 97 34 31 33 95
+78 17 53 28 22 75 31 67 15 94 03 80 04 62 16 14 09 53 56 92
+16 39 05 42 96 35 31 47 55 58 88 24 00 17 54 24 36 29 85 57
+86 56 00 48 35 71 89 07 05 44 44 37 44 60 21 58 51 54 17 58
+19 80 81 68 05 94 47 69 28 73 92 13 86 52 17 77 04 89 55 40
+04 52 08 83 97 35 99 16 07 97 57 32 16 26 26 79 33 27 98 66
+88 36 68 87 57 62 20 72 03 46 33 67 46 55 12 32 63 93 53 69
+04 42 16 73 38 25 39 11 24 94 72 18 08 46 29 32 40 62 76 36
+20 69 36 41 72 30 23 88 34 62 99 69 82 67 59 85 74 04 36 16
+20 73 35 29 78 31 90 01 74 31 49 71 48 86 81 16 23 57 05 54
+01 70 54 71 83 51 54 69 16 92 33 48 61 43 52 01 89 19 67 48}.strip
+
+array = matrix.split("\n").map{|row| row.split(" ").map{|n| n.start_with?("0") ? " #{n[1]}" : n } }
+
+# int SomeArray[20][20] = { {0,0}, {1,2}, {2,4}, {3,6}, {4,8}};
+
+size = array.first.size
+
+cpp_left = "int mSize = #{size};\nint matrix[#{size}][#{size}] = ";
+cpp_right = "{\n" + array.map{|r| r.join(', ') }.map{|r| " {#{r}}" }.join(",\n") + "\n};"
+
+cpp_matrix = cpp_left + cpp_right
+
+puts cpp_matrix
+
+
+

0 comments on commit 9361d76

Please sign in to comment.