Straddling checkerboard: Difference between revisions

=={{header|Java}}==

{{works with|Java|7}}

<lang java>import java.util.Map;

import java.util.regex.*;

public class StraddlingCheckerboard {

final static String[] keyvals = {"H:0", "O:1", "L:2", "M:4", "E:5", "S:6",

"R:8", "T:9", "A:30", "B:31", "C:32", "D:33", "F:34", "G:35", "I:36",

"J:37", "K:38", "N:39", "P:70", "Q:71", "U:72", "V:73", "W:74", "X:75",

"Y:76", "Z:77", ".:78", "/:79", "0:790", "1:791", "2:792", "3:793",

"4:794", "5:795", "6:796", "7:797", "8:798", "9:799"};

final static Map<String, String> val2key = new HashMap<>();

final static Map<String, String> key2val = new HashMap<>();

public static void main(String[] args) {

for (String keyval : keyvals) {

String[] kv = keyval.split(":");

val2key.put(kv[0], kv[1]);

key2val.put(kv[1], kv[0]);

}

String enc = encode("One night-it was on the twentieth of March, "

+ "1888-I was returning");

System.out.println(enc);

System.out.println(decode(enc));

}

static String encode(String s) {

StringBuilder sb = new StringBuilder();

for (String c : s.toUpperCase().split("")) {

c = val2key.get(c);

if (c != null)

sb.append(c);

}

return sb.toString();

}

static String decode(String s) {

Matcher m = Pattern.compile("(79.|3.|7.|.)").matcher(s);

StringBuilder sb = new StringBuilder();

while (m.find()) {

String v = key2val.get(m.group(1));

if (v != null)

sb.append(v);

}

return sb.toString();

}

}</lang>

<pre>139539363509369743061399059745399365901344308320791798798798367430685972839363935

ONENIGHTITWASONTHETWENTIETHOFMARCH1888IWASRETURNING</pre>