start p initial 5 final start 5 initial 4 final start 4 initial 3 final start 3 initial 2 final start 2 initial 1 final start 1 initial 0 final start 0 final end 0 ok 10000 final end 1 ok 10001 final end 2 ok 10002 final end 3 ok 10003 final end 4 ok 10004 final end 5 ok 10005 end p