Data commit

Task/Determine-if-a-string-is-collapsible/Java/determine-if-a-string-is-collapsible.java

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+//  Title:  Determine if a string is collapsible
+
+public class StringCollapsible {
+
+    public static void main(String[] args) {
+        for ( String s : new String[] {
+              "",
+              "\"If I were two-faced, would I be wearing this one?\" --- Abraham Lincoln ",
+              "..1111111111111111111111111111111111111111111111111111111111111117777888",
+              "I never give 'em hell, I just tell the truth, and they think it's hell. ",
+              "                                                    --- Harry S Truman  ",
+              "122333444455555666666777777788888888999999999",
+              "The better the 4-wheel drive, the further you'll be from help when ya get stuck!",
+              "headmistressship"}) {
+            String result = collapse(s);
+            System.out.printf("old:  %2d <<<%s>>>%nnew:  %2d <<<%s>>>%n%n", s.length(), s, result.length(), result);
+        }
+    }
+
+    private static String collapse(String in) {
+        StringBuilder sb = new StringBuilder();
+        for ( int i = 0 ; i < in.length() ; i++ ) {
+            if ( i == 0 || in.charAt(i-1) != in.charAt(i) ) {
+                sb.append(in.charAt(i));
+            }
+        }
+        return sb.toString();
+    }
+
+}