Find All Valid Weekly Work Schedules

Problem: Find All Valid Weekly Work Schedules Given three parameters: workHours: total required working hours in a week, 0 <= workHours <= 56; dayHours: maximum working hours per day, 0 <= dayHours <= 8; pattern: a string of length 7, representing the schedule from Monday to Sunday. Each character in pattern means: '0' to '8': fixed working hours for that day; '?': flexible, can be replaced by any integer from 0 to dayHours. Return all valid schedules. Each schedule is a string of length 7 satisfying: Every ? is replaced by a digit; Daily hours do not exceed dayHours; The total hours over 7 days equals exactly workHours. Output the schedules in lexicographical order. Input Format workHours dayHours pattern Output Format Print one valid schedule per line. If no valid schedule exists, print nothing. Constraints 0 <= workHours <= 56 0 <= dayHours <= 8 pattern.length == 7 pattern[i] is '0' to '8' or '?'. Example Input: 24 4 08??840 Output: 0804840 0813840 0822840 0831840 0840840 Example Input 24 4 08??840 Output 0804840 0813840 0822840 0831840 0840840