Project Euler #18: Maximum path sum I

Question

By starting at the top of the triangle below and moving to adjacent numbers on the row below, the maximum total from top to bottom is 23.

3
7 4
2 4 6
8 5 9 3

That is, 3 + 7 + 4 + 9 = 23.
Find the maximum total from top to bottom of the triangle below:

75
95 64
17 47 82
18 35 87 10
20 04 82 47 65
19 01 23 75 03 34
88 02 77 73 07 63 67
99 65 04 28 06 16 70 92
41 41 26 56 83 40 80 70 33
41 48 72 33 47 32 37 16 94 29
53 71 44 65 25 43 91 52 97 51 14
70 11 33 28 77 73 17 78 39 68 17 57
91 71 52 38 17 14 91 43 58 50 27 29 48
63 66 04 68 89 53 67 30 73 16 69 87 40 31
04 62 98 27 23 09 70 98 73 93 38 53 60 04 23

NOTE: As there are only 16384 routes, it is possible to solve this problem by trying every route. However, Problem 67, is the same challenge with a triangle containing one-hundred rows; it cannot be solved by brute force, and requires a clever method! ;o)

Answer : 1074

Solution

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33

public class Solution { public static void main(String[] args) { System.out.println(new Solution().run()); } public String run() { for (int i = triangle.length - 2; i >= 0; i--) { for (int j = 0; j < triangle[i].length; j++) triangle[i][j] += Math.max(triangle[i + 1][j], triangle[i + 1][j + 1]); } return Integer.toString(triangle[0][0]); } private int[][] triangle = { // Mutable {75}, {95,64}, {17,47,82}, {18,35,87,10}, {20, 4,82,47,65}, {19, 1,23,75, 3,34}, {88, 2,77,73, 7,63,67}, {99,65, 4,28, 6,16,70,92}, {41,41,26,56,83,40,80,70,33}, {41,48,72,33,47,32,37,16,94,29}, {53,71,44,65,25,43,91,52,97,51,14}, {70,11,33,28,77,73,17,78,39,68,17,57}, {91,71,52,38,17,14,91,43,58,50,27,29,48}, {63,66, 4,68,89,53,67,30,73,16,69,87,40,31}, { 4,62,98,27,23, 9,70,98,73,93,38,53,60, 4,23}, }; }