I was trying out the JetBrains course of Java Core. This is the exercise:

Let's implement the simplest search engine possible ever. It should search for a specific word in a multi-word input line. The input line contains several words separated by a space. The words are numbered according to their order, with the first word having index 1. Consider that all the words in the line are unique, so there can be no repetition. Write a simple program that reads two lines: a line of words and a line containing the search word. The program must search in the first line for a word specified in the second one. The program should output the index of the specified word. If there is no such word in the first line, the program should print Not Found. Please remember that indexes start from 1! You should output exactly one line. The lines that start with > represent the user input. Note that these symbols are not part of the input.

Example 1:

"> first second third fourth" "> third" "3"

Example 2:

"> cat dog and mouse" "> elephant" "Not found"

This is my code:

package search;
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        String sc1 = scanner.nextLine();
        String[] splited = sc1.split("\\s ");

        String sc2 = scanner.nextLine();
        int index = 0;
        boolean flag = false;

        for (int i = 0; i <= splited.length - 1; i  ) {
            if (sc2.contains(splited[i])) {
                flag = true;
                index = i 1; //line updated, same result
            }
        }
        
        if (flag) {
           System.out.println(index);
            }
        else {
           System.out.println("not found ");
        }
    }            
}

And this is the answer:

Wrong answer in test #1

Please find below the output of your program during this failed test. Note that the '>' character indicates the beginning of the input line.

"---"

"> hello my name is alex"

"> my"

"1"

Update: Thanks a lot for your comments @shriakhilc and @Gardener. I updated the code, as per Gardener's advice, and now it gives me this example:

what a beautiful place what 2

What could I do to make it count from 1? (I also tried changing the initial values of both i and index separately and doesn't work either, also modified length but nothing either.)

CodePudding user response：

You cannot make array indexes start at 1 in Java, you will have to adjust the result.

I spotted several issues in your code, but none is related to your problem:

1. You should replace the condition of your loop i <= splited.length - 1 with the simpler i < splited.length
2. Rename flag to found as this is what the flag means.
3. You should extend your loop end condition with flag so you stop searching after the first "hit": (i < splited.length) && !found

Now for your actual problem: I would suggest that you simply store the value of i into index and do the calculation only at the output, so inside the if in the loop just set index = i; and add 1 just on the output: System.out.println(index 1);

Make sure that with all your attempts to fix the code, you add the 1 only once to index, your update sounds as if you applied the fix twice.

Update Also trim your input string to prevent empty array elements at the beginning of the splitted array: String[] splited = sc1.trim().split("\\s ");