blob: ee04d5c6059262dad363b44d4a2230c2d1160c20 (
plain)
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
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
|
//
// Exercise:
// You are given m x n character matrix consists of O and X only.
// Write a script to count the total number of X surrounded by O only.
// Print 0 if none found.
//
//
// Read in the board:
// - Read STDIN
// - Split by newlines
// - Split each line on spaces
// - Map an 'X' to a 1, 'O' to a 0.
// - Add a 0 to the beginning and end of each line.
//
let fs = require ("fs");
let board = fs . readFileSync (0) . toString () . trim () . split ("\n") .
map (line => (line . split (" ")) . map (c => c == "X" ? 1 : 0)) .
map (line => ([0] . concat (line) . concat ([0])));
//
// Add top and bottom with 0s
//
board . push (board [0] . map (x => 0));
board . unshift (board [0] . map (x => 0));
let count = 0;
//
// Iterate over the cells of the board board, skipping cells on the edge
// (as we added them). For each 1, check the 8 cells surrounding the cell
// (this will never be outside of the board). If one of the neighbouring
// cells is a 1, move on the next cell. If no neighbouring cell is 1,
// we add 1 to the count.
//
for (let x = 1; x < board . length - 1; x ++) {
ELEMENT:
for (let y = 1; y < board [x] . length - 1; y ++) {
if (!board [x] [y]) {
continue;
}
for (let dx = -1; dx <= 1; dx ++) {
for (let dy = -1; dy <= 1; dy ++) {
if (dx == 0 && dy == 0) {
continue;
}
if (board [x + dx] [y + dy]) {
continue ELEMENT;
}
}
}
count ++;
}
}
//
// Print the results.
//
console . log (count);
|
