The challenge
Simple, remove the spaces from the string, then return the resultant string.
The solution in Java code
class Solution { static String noSpace(final String x) { return x.replace(" ", ""); } }
An alternative:
class Solution { static String noSpace(final String x) { return x.replaceAll("\\s+",""); } }
Test cases to validate our Java solution
import org.junit.Test; import java.util.Random; import static org.junit.Assert.assertEquals; public class SolutionTest { @Test public void testSomething() { assertEquals("8j8mBliB8gimjB8B8jlB", Solution.noSpace("8 j 8 mBliB8g imjB8B8 jl B")); assertEquals("88Bifk8hB8BB8BBBB888chl8BhBfd", Solution.noSpace("8 8 Bi fk8h B 8 BB8B B B B888 c hl8 BhB fd")); assertEquals("8aaaaaddddr", Solution.noSpace("8aaaaa dddd r ")); assertEquals("jfBmgklf8hg88lbe8", Solution.noSpace("jfBm gk lf8hg 88lbe8 ")); assertEquals("8jaam", Solution.noSpace("8j aam")); } private static final String chars = "abc defg hij klm no pq rstuvw xyz"; @Test public void randomTests() { Random random = new Random(); StringBuilder sb = new StringBuilder(); for (int i = 0; i < 20; i++) { int length = random.nextInt(15) + 1; for (int j = 0; j < length; j++) { int index = random.nextInt(chars.length()); sb.append(chars.charAt(index)); } String input = sb.toString(); sb.setLength(0); assertEquals(input.replaceAll(" ", ""), Solution.noSpace(input)); } } }