gistfile1.java

//"abc" "bc" -> [ 0 ]
//"abc" "c" -> [ 0, 1 ]
//"abac" -> "aac" -> [ 1 ]
//"aabc" -> "abc" -> [ 0 ] *or* [ 1 ]

public static List getDeletedChar(String a, String b) {
        List results = new ArrayList();
        int charIndex;
        int cursorPos = 0;
        for (int i = 0; i < b.length(); i++) {
            charIndex = a.indexOf(b.charAt(i), cursorPos);
            for (int j = cursorPos; j < charIndex; j++) {
                results.add(j);
            }
            cursorPos = charIndex + 1;
        }
        while(cursorPos < a.length()){
            results.add(cursorPos++);
        }

        return results;
    }