Question

    import java.io.PrintStream;
import java.util.Arrays;

public class joker {
   public static int smallest(int[] v1, int[] v2) {
      return 0;
   }

   public static int[] convert1(String str) {
      return new int[1];
   }

   public static String convert2(int[] v) {
      return "";
   }

   public static void main(String[] args) {
      testSmallest();
      testConvert();
   }

   public static void testSmallest() {
      System.out.println("Testing your method smallest(...)");
      int[][] testVectors1 = new int[][]{{1, 2, 3}, {1, 2, 3, 4}, {1, 2, 3}, {1, 2, 3}, {2, 3, 4}};
      int[][] testVectors2 = new int[][]{{1, 2, 3, 4}, {1, 2, 3}, {1, 2, 3}, {2, 3, 4}, {1, 2, 3}};
      int[] expectedOutcomes = new int[]{1, 2, 0, 1, 2};
      if (expectedOutcomes.length != testVectors2.length || expectedOutcomes.length != testVectors1.length || testVectors1.length != testVectors2.length) {
         System.out.println("All tables must have the same # of tests");
         System.exit(-1);
      }

      int nTests = expectedOutcomes.length;

      for(int test = 0; test < nTests; ++test) {
         int observedOutcome = smallest(testVectors1[test], testVectors2[test]);
         PrintStream var10000 = System.out;
         Arrays.toString(testVectors1[test]).print(Arrays.toString(testVectors2[test]));
         if (observedOutcome == expectedOutcomes[test]) {
            System.out.println(" SUCCEEDED");
         } else {
            System.out.println(" FAILED");
         }
      }

   }

   public static void testConvert() {
      String[] strings = new String[]{"", "0", "9", "12", "123"};
      int[][] vectors = new int[][]{new int[0], {0}, {9}, {1, 2}, {1, 2, 3}};
      System.out.println("\nTesting your method convert1(...)");
      if (vectors.length != strings.length) {
         System.out.println("All tables must have the same # of tests");
         System.exit(-1);
      }

      PrintStream var10000;
      int test;
      for(test = 0; test < strings.length; ++test) {
         int[] observed = convert1(strings[test]);
         var10000 = System.out;
         test.print(strings[test]);
         System.out.println(Arrays.equals(observed, vectors[test]) ? "SUCCEEDED" : "FAILED");
      }

      System.out.println("\nTesting your method convert2(...)");

      for(test = 0; test < vectors.length; ++test) {
         String observed = convert2(vectors[test]);
         var10000 = System.out;
         test.print(Arrays.toString(vectors[test]));
         System.out.println(observed.equals(strings[test]) ? "SUCCEEDED" : "FAILED");
      }

   }
}

Answer 1

        /**
         * This method returns 1 if vector v1 is the "smallest", 2 if it is vector v2,
         * or 0 otherwise. We define "smallest" as follows; If one of the vector has
         * fewer elements than the other, it is the smallest one. If both are the same
         * size, then we look at every element one by one in order. As soon as one of
         * the two vectors has an element that is < than the corresponding element from
         * the other vector, then it is recognized as the "smallest" one by our method.
         **/
        public static int smallest(int[] v1, int[] v2) {
                
                if(v1.length < v2.length) {
                        return 1;
                } else if(v1.length > v2.length) {
                        return 2;
                } else {
                        
                        for(int i=0; i<v1.length; i++) {
                                
                                if(v1[i] < v2[i]) {
                                        return 1;
                                } else if(v1[i] > v2[i]) {
                                        return 2;
                                }
                                
                        }
                        
                }
                
                return 0; // always returns 0 for now, replace this with your code
        }// end method smallest

        /**
         * This method takes a string that is guaranteed to be made only of digits,
         * without spaces or anything else. Examples; "123" or "0" Your goal is to
         * create a new array of int values that will hold each of the digits specified
         * in the String. Example; if the string passed is "123" your returned array
         * should contain the int value 1 at index 0, the value 2 at index 1, and the
         * value 3 at index 2. Once you are done, return the reference to your newly
         * created array of int values.
         **/
        public static int[] convert1(String str) {
                
                int result[] = new int[str.length()];
                
                for(int i=0; i<str.length(); i++) {
                        result[i] = str.charAt(i) - '0';
                }
                
                return result; // always returns an array with 1 element for now, replace this with your code
        }// end method convert1

        /**
         * This method does the opposite work of the above convert1 method. It takes a
         * vector of single-digit int values and return a string with all these digits
         * one after the other. If one of the values in the vector is not in the range 0
         * to 9 inclusive, then simply have this method return an empty string as result
         * instead.
         **/
        public static String convert2(int[] v) {
                
                String s = "";
                for(int x: v) {
                        if(x < 0 || x > 9) {
                                return "";
                        }
                        s += x;
                }
                
                return s; // always returns an empty string for now, replace this with your code
        }// end method convert2

**************************************************
Your test class is having compilation problem.. Hence i just gave the correct code for the methods.

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