Why is essentially identical code not executed?

Question

Java

Good day.
There is a simple task: take a string and remove from it all substrings of 3 characters. Substrings start with 'y' and end with 'k', and 'yakabc' would, for example, be 'abc'.
The correct solution looks like this:

public String stringСut(String str) {
  String result = "";
  
  for (int i=0; i<str.length(); i++) {
    if (i+2<str.length() && str.charAt(i)=='y' && str.charAt(i+2)=='k') {
      i =  i + 2;
    } else {
      result = result + str.charAt(i);
    }
  }
  
  return result;
}

My solution is very similar, just goes from 'if not equal':

public String stringСut(String str) {
  String result = "";
  
  for (int i=0; i<str.length(); i++) {
    if (i+2<str.length() && str.charAt(i)!='y' && str.charAt(i+2)!='k') {
      result = result + str.charAt(i);
    } else {
      i = i + 2;
    }
  }
  
  return result;
}

This code compiles, but only an empty string is returned. With what it can be connected?
Thanks to.

Answer 1

You incorrectly "inverted" conditions.
It should turn out something like:

(i+2<str.length() && (str.charAt(i)!='y' || str.charAt(i+2)!='k'))