Example 1: testing compiler.
Example 1: minor modifying.
Example 1: finished.
Example 2: completed.
Example 3: completed.
Example 4: start.
Example 4: how to generate random.
Example 4: guessing step.
Example 4: game completed.
Example 4: GCD start.
Example 4: non recursive euclide function.
Example 4: finished.
Example 5: math quize.
Example 5: factorials completed.
Example 6: completed.