The first line contains the instance name which represents the general problem characteristics of the instance as follows:
instance id _ number of patients _ percentage of existing patients _ network size _ task repartition _ the number of graph _ roster id

The following lines are the list of the problem characteristics as data input for the code
- number of patients {50,100,150}
- number of tasks
- number of nurses
- number of working shifts
- planning horizon : the length of optimization horizon
- percentage of existing patients {0.3,0.5}
- percentage of middle day tasks : to represents the task repartition {1=equal repartition, 0.8=dense repartition}
- area of service : to represents the network size {1=normal area, 2=large area}

All information in the instance files are separated by tab "\t".
Each block of data is started by "$" and a keyword describing the content of the corresponding block. Each list starts with index 0.

"$tasks" - contains the list of tasks. Each line represents one task with the following information:
- task id
- patient id
- day of service, started by 1 for Monday
- service duration (in minutes)
- qualification requirement
- the start of the time window
- the end of the time window

"$travel_times" - the traveling times from one patient location (including hospital) to another patient location

"$shift_types" - contains the list of working shift. Each line represents one type of working shift with the following information:
- shift id
- the start time of the shift
- the end time of the shift

"$nurse_qualifications" - contains the list of nurses with their highest qualifications. Each line represent one nurse:
- nurse id
- highest qualification acquired

"$nurse_availabilities" - contains the list of nurses and their availabilities during the optimization horizon. Each line represents the availability of each nurse of each type of working shift during the optimization horizon as follows:
- nurse id
- shift id
- the next column until the last column contains binary values for each day of the optimization horizon, 1 being available and 0 otherwise

The following lines contain the information from the baseline roster

"$nurse_roster" - contains the list of nurses and their working schedule during the optimization horizon from the baseline roster. Each line represents the assignment to each nurse for each type of working shift during the optimization horizon as follows:
- nurse id
- shift id
- the next column until the last column contains binary values for each day of the optimization horizon, 1 being assigned and 0 otherwise


"$consecutive_days" - represents the stepping horizon information related to the number of consecutive working days at the border of the optimization horizon from the baseline roster. Each line represents the following information:
- nurse id
- the number of consecutive days by far before the beginning of optimization horizon (at the end of reference horizon), if any
- the number of consecutive days at the beginning of the look-ahead horizon, if any

"$isolated_days" - contains the stepping horizon information related to isolated working days. Each line represents the following information:
- nurse id
- binary value regarding the assignment of the nurse on Saturday of reference horizon, 1 being assigned to a working shift, and 0 is having a day-off
- binary value regarding the assignment of the nurse on Sunday of reference horizon, 1 being assigned to a working shift, and 0 is having a day-off
- binary value regarding the assignment of the nurse on Monday of look-ahead horizon, 1 being assigned to a working shift, and 0 is having a day-off
- binary value regarding the assignment of the nurse on Tuesday of look-ahead horizon, 1 being assigned to a working shift, and 0 is having a day-off

"$forbidden_rotation" - represents the stepping horizon information related to forbidden shift rotation constraints. Each line represents the following information:
- nurse id
- binary value, 1 if it is allowed to assigned the nurse to the early shift of Monday in the optimization horizon, 0 if forbidden
- binary value, 1 if it is allowed to assigned the nurse to the late shift of Sunday in the optimization horizon, 0 if forbidden

the following lines contain the information about the patients

"$patients" - list of patients with the following information:
- patient id
- x coordinate 
- y coordinate
- type of patients {0=hospital, 1=existing patient, 2=potential patient}
- type of patient visits {0= hospital, 1=Type I, 2=Type II, 3=Type III, 4=Type IV}