CATCH no_voucher flag_no_active_voucher 1
LOAD get_vouchers 0
MAP get_vouchers
MOUT back 0
MOUT quit 99
MNEXT next 88
MPREV prev 98
HALT
INCMP > 88
INCMP < 98
INCMP _ 0
INCMP quit 99
LOAD calculate_max_pay_debt 0
RELOAD calculate_max_pay_debt
CATCH . flag_incorrect_voucher 1
INCMP calculate_max_pay_debt *