1+ let gridText = `08 02 22 97 38 15 00 40 00 75 04 05 07 78 52 12 50 77 91 08
2+ 49 49 99 40 17 81 18 57 60 87 17 40 98 43 69 48 04 56 62 00
3+ 81 49 31 73 55 79 14 29 93 71 40 67 53 88 30 03 49 13 36 65
4+ 52 70 95 23 04 60 11 42 69 24 68 56 01 32 56 71 37 02 36 91
5+ 22 31 16 71 51 67 63 89 41 92 36 54 22 40 40 28 66 33 13 80
6+ 24 47 32 60 99 03 45 02 44 75 33 53 78 36 84 20 35 17 12 50
7+ 32 98 81 28 64 23 67 10 26 38 40 67 59 54 70 66 18 38 64 70
8+ 67 26 20 68 02 62 12 20 95 63 94 39 63 08 40 91 66 49 94 21
9+ 24 55 58 05 66 73 99 26 97 17 78 78 96 83 14 88 34 89 63 72
10+ 21 36 23 09 75 00 76 44 20 45 35 14 00 61 33 97 34 31 33 95
11+ 78 17 53 28 22 75 31 67 15 94 03 80 04 62 16 14 09 53 56 92
12+ 16 39 05 42 96 35 31 47 55 58 88 24 00 17 54 24 36 29 85 57
13+ 86 56 00 48 35 71 89 07 05 44 44 37 44 60 21 58 51 54 17 58
14+ 19 80 81 68 05 94 47 69 28 73 92 13 86 52 17 77 04 89 55 40
15+ 04 52 08 83 97 35 99 16 07 97 57 32 16 26 26 79 33 27 98 66
16+ 88 36 68 87 57 62 20 72 03 46 33 67 46 55 12 32 63 93 53 69
17+ 04 42 16 73 38 25 39 11 24 94 72 18 08 46 29 32 40 62 76 36
18+ 20 69 36 41 72 30 23 88 34 62 99 69 82 67 59 85 74 04 36 16
19+ 20 73 35 29 78 31 90 01 74 31 49 71 48 86 81 16 23 57 05 54
20+ 01 70 54 71 83 51 54 69 16 92 33 48 61 43 52 01 89 19 67 48` ;
21+
22+ //first, we parse the text copied directly from the problem page into a 2d array called "grid"
23+
24+ let grid = new Array ( 10 ) ;
25+
26+ let rows = gridText . split ( "\n" ) ;
27+
28+ for ( let i = 0 ; i < rows . length ; i ++ ) {
29+ grid [ i ] = rows [ i ] . split ( " " ) ;
30+ }
31+
32+ let highestProduct = 1 ; //accumulator variable to hold the highest product found so far as we traverse the grid
33+
34+ //next, we traverse the grid
35+ //check adjacent products of the 3 elements up, down, left, right, diagonally bottom right, and diagonally bottom left of each element (if it's possible to do so)
36+ //if a product is higher than the highestProduct found so far, update highestProduct
37+
38+ for ( let row = 0 ; row < grid . length ; row ++ ) {
39+ for ( let col = 0 ; col < grid [ row ] . length ; col ++ ) {
40+ //3 up
41+ if ( row >= 3 ) {
42+ let product = parseInt ( grid [ row ] [ col ] ) * parseInt ( grid [ row - 1 ] [ col ] ) * parseInt ( grid [ row - 2 ] [ col ] ) * parseInt ( grid [ row - 3 ] [ col ] ) ;
43+
44+ if ( product > highestProduct ) {
45+ highestProduct = product ;
46+ }
47+ }
48+
49+ //3 down
50+ if ( row < grid . length - 3 ) {
51+ let product = parseInt ( grid [ row ] [ col ] ) * parseInt ( grid [ row + 1 ] [ col ] ) * parseInt ( grid [ row + 2 ] [ col ] ) * parseInt ( grid [ row + 3 ] [ col ] ) ;
52+
53+ if ( product > highestProduct ) {
54+ highestProduct = product ;
55+ }
56+ }
57+
58+ //3 left
59+ if ( col >= 3 ) {
60+ let product = parseInt ( grid [ row ] [ col ] ) * parseInt ( grid [ row ] [ col - 1 ] ) * parseInt ( grid [ row ] [ col - 2 ] ) * parseInt ( grid [ row ] [ col - 3 ] ) ;
61+
62+ if ( product > highestProduct ) {
63+ highestProduct = product ;
64+ }
65+ }
66+
67+ //3 right
68+ if ( col < grid [ row ] . length - 3 ) {
69+ let product = parseInt ( grid [ row ] [ col ] ) * parseInt ( grid [ row ] [ col + 1 ] ) * parseInt ( grid [ row ] [ col + 2 ] ) * parseInt ( grid [ row ] [ col + 3 ] ) ;
70+
71+ if ( product > highestProduct ) {
72+ highestProduct = product ;
73+ }
74+ }
75+
76+ //3 diagonal bottom right
77+ if ( ( row < grid . length - 3 ) && ( col < grid [ row ] . length - 3 ) ) {
78+ let product = parseInt ( grid [ row ] [ col ] ) * parseInt ( grid [ row + 1 ] [ col + 1 ] ) * parseInt ( grid [ row + 2 ] [ col + 2 ] ) * parseInt ( grid [ row + 3 ] [ col + 3 ] ) ;
79+
80+ if ( product > highestProduct ) {
81+ highestProduct = product ;
82+ }
83+ }
84+
85+ //3 diagonal bottom left
86+ if ( ( row < grid . length - 3 ) && ( col >= 3 ) ) {
87+ let product = parseInt ( grid [ row ] [ col ] ) * parseInt ( grid [ row + 1 ] [ col - 1 ] ) * parseInt ( grid [ row + 2 ] [ col - 2 ] ) * parseInt ( grid [ row + 3 ] [ col - 3 ] ) ;
88+
89+ if ( product > highestProduct ) {
90+ highestProduct = product ;
91+ }
92+ }
93+ }
94+ }
95+
96+ console . log ( highestProduct ) ; // our answer!
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