[Help-glpk] Is there a simpler way to write this s.t. in MathProg- ANSWER FOUND

[P PO1434]

Mucking around, I think I found the answer to my first question above - for 
anyone that is interested it's one generic solution to workload shift 
coverage constraint definitions ie. you have demand during a day, and you 
need to cover the demand with staff working varying shift lengths.

# example: 0..47 periods in half hr blocks representing time of day (00:00 
to 23:30)
# shifts: shift lengths to be used eg. 4 and 8, or 4..10 hr shifts
# perstart would be 0 in this case

# AND (most important) perdpershift = how many periods in 1 shift length 
unit ie. if hourly shifts,
# and 1/2hr time increments in day = 2

subject to c{i in Periods}:
	 sum{shift in Shifts,period in Periods : period >= max(perstart,(i-shift * 
perdpershift +1)) and period<=i}  starts[period,shift]>=demand[i];

Pete