in JAVA

why my code is not running

Scanner k = new Scanner(System.in); System.out.println("Please enter a string: "); String str = k.nextLine(); System.out.println("Please enter a character: "); String input = k.nextLine(); char a = input.charAt(0); int count = 0; for(int i= 0;i<= str.length(); i++) { if(str.charAt(i) == a) count ++; } if(count <= 0) System.out.println("Character not found in the string "); else System.out.println("The number of character appears in the string is " + count);