Data commit

Task/Brace-expansion/Java/brace-expansion.java

@@ -0,0 +1,46 @@
+public class BraceExpansion {
+
+    public static void main(String[] args) {
+        for (String s : new String[]{"It{{em,alic}iz,erat}e{d,}, please.",
+            "~/{Downloads,Pictures}/*.{jpg,gif,png}",
+            "{,{,gotta have{ ,\\, again\\, }}more }cowbell!",
+            "{}} some }{,{\\\\{ edge, edge} \\,}{ cases, {here} \\\\\\\\\\}"}) {
+            System.out.println();
+            expand(s);
+        }
+    }
+
+    public static void expand(String s) {
+        expandR("", s, "");
+    }
+
+    private static void expandR(String pre, String s, String suf) {
+        int i1 = -1, i2 = 0;
+        String noEscape = s.replaceAll("([\\\\]{2}|[\\\\][,}{])", "  ");
+        StringBuilder sb = null;
+
+        outer:
+        while ((i1 = noEscape.indexOf('{', i1 + 1)) != -1) {
+            i2 = i1 + 1;
+            sb = new StringBuilder(s);
+            for (int depth = 1; i2 < s.length() && depth > 0; i2++) {
+                char c = noEscape.charAt(i2);
+                depth = (c == '{') ? ++depth : depth;
+                depth = (c == '}') ? --depth : depth;
+                if (c == ',' && depth == 1) {
+                    sb.setCharAt(i2, '\u0000');
+                } else if (c == '}' && depth == 0 && sb.indexOf("\u0000") != -1)
+                    break outer;
+            }
+        }
+        if (i1 == -1) {
+            if (suf.length() > 0)
+                expandR(pre + s, suf, "");
+            else
+                System.out.printf("%s%s%s%n", pre, s, suf);
+        } else {
+            for (String m : sb.substring(i1 + 1, i2).split("\u0000", -1))
+                expandR(pre + s.substring(0, i1), m, s.substring(i2 + 1) + suf);
+        }
+    }
+}