Question

String[] letters  = {"A", "B", "C", "D", "E", "F", "G", "H", "I", "L"};

Scanner inp = new Scanner(System.in);
String input = (inp.nextLine());
String[] cord = input.split("");

for(int x = 0; x < 10; x++)
    if(letters[x] == cord[1])
        System.out.println("Fk yeah!");

Why the Fk yeah! never happens if I input one of A-L letters?

Answer 1

Strings are objects. The == compares objects by reference, not by their internal value.

There are 2 solutions:

1. Use String#equals() method instead to compare the value of two String objects.

   if (letters[x].equals(cord[1]))
   

2. Use char instead of String. It’s a primitive, so == will work.

   char[] letters  = {'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'L'};
   
   Scanner inp = new Scanner(System.in);
   String input = (inp.nextLine());
   char[] cord = input.toCharArray();
   
   for (int x = 0; x < 10; x++)
       if (letters[x] == cord[1])
           System.out.println("Fk yeah!");