initial commit

java/reverse/FastReverseTest.java

@@ -0,0 +1,87 @@
+package reverse;
+
+import base.ExtendedRandom;
+import base.Named;
+import base.Selector;
+import base.TestCounter;
+import wordStat.WordStatTest;
+
+import java.util.Arrays;
+import java.util.function.BiFunction;
+import java.util.function.LongBinaryOperator;
+import java.util.stream.Collectors;
+import java.util.stream.IntStream;
+
+/**
+ * @author Georgiy Korneev (kgeorgiy@kgeorgiy.info)
+ */
+public final class FastReverseTest {
+    // === 3637
+
+    private static final Named<BiFunction<ExtendedRandom, Integer, String>> OCT = Named.of("",
+            (r, i) -> r.nextBoolean() ? Integer.toString(i) : Integer.toOctalString(i) + (r.nextBoolean() ? "o" : "O")
+    );
+    private static final Named<BiFunction<ExtendedRandom, Integer, String>> DEC = Named.of("", (r, i) -> Integer.toString(i));
+
+    private static final Named<String> PUNCT = Named.of(
+            "",
+            IntStream.range(0, Character.MAX_VALUE)
+                    .filter(ch -> ch == ' ' || Character.getType(ch) == Character.START_PUNCTUATION || Character.getType(ch) == Character.END_PUNCTUATION)
+                    .filter(ch -> ch != 13 && ch != 10)
+                    .mapToObj(Character::toString)
+                    .collect(Collectors.joining())
+    );
+
+    public static final Named<ReverseTester.Op> MIN_C = Named.of("MinC", scan2((a, b) -> b));
+    public static final Named<ReverseTester.Op> MIN = Named.of("Min", scan2(Math::min));
+
+    private static ReverseTester.Op scan2(final LongBinaryOperator reduce) {
+        return ints -> {
+            // This code is intentionally obscure
+            final int length = Arrays.stream(ints).mapToInt(r -> r.length).max().orElse(0);
+            final long[] cs = new long[length];
+            final long[] cc = new long[length + 1];
+            Arrays.fill(cs, Integer.MAX_VALUE);
+            Arrays.fill(cc, Integer.MAX_VALUE);
+            //noinspection NestedAssignment
+            final long[][] rows = range(ints.length).mapToObj(i -> {
+                        range(ints[i].length).forEachOrdered(j -> cc[j] = reduce.applyAsLong(
+                                cc[j + 1],
+                                cs[j] = Math.min(cs[j], ints[i][j])
+                        ));
+                        return Arrays.copyOf(cc, ints[i].length);
+                    })
+                    .toArray(long[][]::new);
+            return range(ints.length).mapToObj(i -> rows[i]).toArray(long[][]::new);
+        };
+    }
+
+    private static IntStream range(final int length) {
+        return IntStream.iterate(length - 1, i -> i >= 0, i -> i - 1);
+    }
+    
+
+    // === Common
+
+    public static final int MAX_SIZE = 1_000_000 / TestCounter.DENOMINATOR / TestCounter.DENOMINATOR;
+
+    public static final Selector SELECTOR = new Selector(FastReverseTest.class)
+            .variant("Base", ReverseTester.variant(MAX_SIZE, ReverseTest.REVERSE))
+            .variant("3637", ReverseTester.variant(MAX_SIZE, "", MIN_C, OCT, DEC, PUNCT))
+            .variant("3839", ReverseTester.variant(MAX_SIZE, "", MIN, OCT, DEC, PUNCT))
+            .variant("3435", ReverseTester.variant(MAX_SIZE, ReverseTest.ROTATE, PUNCT))
+            .variant("3233", ReverseTester.variant(MAX_SIZE, ReverseTest.EVEN, PUNCT))
+            .variant("4142", ReverseTester.variant(MAX_SIZE, ReverseTest.AVG, PUNCT))
+            .variant("4749", ReverseTester.variant(MAX_SIZE, ReverseTest.SUM, PUNCT))
+
+            ;
+
+
+    private FastReverseTest() {
+    }
+
+    public static void main(final String... args) {
+        SELECTOR.main(args);
+        WordStatTest.main(args);
+    }
+}