Fork Seq [Fork Assign [Fork (Letter "x") [],Fork (Letter "1") []],Fork Assign [Fork (Letter "y") [],Fork (Letter "a") []],Fork Assign [Fork (Letter "z") [],Fork (Letter "b") []],Fork While [Fork Not [Fork Equ [Fork (Letter "z") [],Fork (Letter "0") []]],Fork If [Fork Equ [Fork Mod [Fork (Letter "z") [],Fork (Letter "2") []],Fork (Letter "0") []],Fork Seq [Fork Assign [Fork (Letter "y") [],Fork Times [Fork (Letter "y") [],Fork (Letter "y") []]],Fork Assign [Fork (Letter "z") [],Fork Div [Fork (Letter "z") [],Fork (Letter "2") []]]],Fork Seq [Fork Assign [Fork (Letter "x") [],Fork Times [Fork (Letter "x") [],Fork (Letter "y") []]],Fork Assign [Fork (Letter "z") [],Fork Minus [Fork (Letter "z") [],Fork (Letter "1") []]]]]]]