Solve triangle solitaire puzzle: Difference between revisions

=={{header|D}}==

{{trans|Ruby}}

<lang d>import std.stdio, std.array, std.string, std.range, std.algorithm;

immutable N = [0,1,1,1,1,1,1,1,1,1,1,1,1,1,1];

immutable G = [[0,1,3],[0,2,5],[1,3,6],[1,4,8],[2,4,7],[2,5,9],

[3,4,5],[3,6,10],[3,7,12],[4,7,11],[4,8,13],[5,8,12],

[5,9,14],[6,7,8],[7,8,9],[10,11,12],[11,12,13],[12,13,14]];

string b2s(in int[] n) pure @safe {

static immutable fmt = iota(6)

.map!(i => " ".replicate(5 - i) ~ "%d ".replicate(i))

.join("\n");

return fmt.format(n[0], n[1], n[2], n[3], n[4], n[5], n[6],

n[7], n[8], n[9], n[10], n[11], n[12], n[13], n[14]);

}

string solve(in int[] n, in int i, in int[] g) pure @safe {

if (i == N.length - 1)

return "\nSolved";

if (n[g[1]] == 0)

return null;

string s;

if (n[g[0]] == 0) {

if (n[g[2]] == 0)

return null;

s = "\n%d to %d\n".format(g[2], g[0]);

} else {

if (n[g[2]] == 1)

return null;

s = "\n%d to %d\n".format(g[0], g[2]);

}

auto a = n.dup;

foreach (const gi; g)

a[gi] = 1 - a[gi];

string l;

foreach (const gi; G) {

l = solve(a, i + 1, gi);

if (!l.empty)

break;

}

return l.empty ? l : (s ~ b2s(a) ~ l);

}

void main() @safe {

b2s(N).write;

string l;

foreach (const g; G) {

l = solve(N, 1, g);

if (!l.empty)

break;

}

writeln(l.empty ? "No solution found." : l);

}</lang>

{{out}}

<pre>

0

1 1

1 1 1

1 1 1 1

1 1 1 1 1

3 to 0

1

0 1

0 1 1

1 1 1 1

1 1 1 1 1

8 to 1

1

1 1

0 0 1

1 1 0 1

1 1 1 1 1

10 to 3

1

1 1

1 0 1

0 1 0 1

0 1 1 1 1

1 to 6

1

0 1

0 0 1

1 1 0 1

0 1 1 1 1

11 to 4

1

0 1

0 1 1

1 0 0 1

0 0 1 1 1

2 to 7

1

0 0

0 0 1

1 1 0 1

0 0 1 1 1

9 to 2

1

0 1

0 0 0

1 1 0 0

0 0 1 1 1

0 to 5

0

0 0

0 0 1

1 1 0 0

0 0 1 1 1

6 to 8

0

0 0

0 0 1

0 0 1 0

0 0 1 1 1

13 to 11

0

0 0

0 0 1

0 0 1 0

0 1 0 0 1

5 to 12

0

0 0

0 0 0

0 0 0 0

0 1 1 0 1

11 to 13

0

0 0

0 0 0

0 0 0 0

0 0 0 1 1

14 to 12

0

0 0

0 0 0

0 0 0 0

0 0 1 0 0

Solved</pre>