algorithms

 1. Find the common number between different int array.

2. Find the same String between different String array. How about if the arrays are super fast, say the duplicate name between US and Canada? two big files

3. Query a LOL player's statistics

4. Display photos

    Display photos with username/password

    Display photos with username/password (no hack/partly)

boolean/int

+-*/ ++ --

== != > < >= <=

&& ||

if/else

swtich(expression){

case c1:

..break;

default:

}

array

For loop

recursion

constructor

static

Math.sqrt(x*x+y*y)

calculate what day after 100 days

read file/write file

Swing