That's because the Scanner.nextInt method does not consume the last newline character of your input, and thus that newline is consumed in the next call to Scanner.nextLine.
You will encounter the similar behaviour when you use "Scanner.nextLine" after Scanner.next() or any "Scanner.nextFoo" method.
you read the input through Scanner.nextLine and convert your input to the proper format you need. For examples, to an integer using "Integer.parseInt(String)" method.
int option = 0;
try {
option = Integer.parseInt(input.nextLine());
} catch (NumberFormatException e) {
e.printStackTrace();
}
String str1 = input.nextLine();