In total tardiness problem, problem hardness is defined by (R, T) combinations. 
R : Range of due date,  is taken from the set {0.2, 0.4, 0.6, 0.8, 1.0}
T : Tardiness Factor, is taken from the set {0.2, 0.4, 0.6, 0.8}

Thus, there are 20 different combinations for (R, T) pairs. 
10 replicants are taken for each (R, T) combination, 
making 200 different test files for each number of jobs.

The names of the input files also have the (R, T) information. 
The input file names have the following structure :
inp***.## 
        where *** denote the number of jobs (like inp100.## for 100 job case)
 	and ## denote the problem hardness :
	between   1 -  10 : (R, T) = (0.2, 0.2)
		 11 -  20 : (R, T) = (0.2, 0.4) 
		 21 -  30 : (R, T) = (0.2, 0.6)
		 31 -  40 : (R, T) = (0.2, 0.8)
		 41 -  50 : (R, T) = (0.4, 0.2)
		 51 -  60 : (R, T) = (0.4, 0.4)
		 61 -  70 : (R, T) = (0.4, 0.6)
		 71 -  80 : (R, T) = (0.4, 0.8)
		 81 -  90 : (R, T) = (0.6, 0.2)
		 91 - 100 : (R, T) = (0.6, 0.4)
		101 - 110 : (R, T) = (0.6, 0.6)
		111 - 120 : (R, T) = (0.6, 0.8)
		121 - 130 : (R, T) = (0.8, 0.2)
		131 - 140 : (R, T) = (0.8, 0.4)
		141 - 150 : (R, T) = (0.8, 0.6)
		151 - 160 : (R, T) = (0.8, 0.8)
		161 - 170 : (R, T) = (1.0, 0.2)
		171 - 180 : (R, T) = (1.0, 0.4)
		181 - 190 : (R, T) = (1.0, 0.6)
		191 - 200 : (R, T) = (1.0, 0.8)

Thus for example inp200.24 corresponds to an instance with 200 jobs and 
which is from (R, T) = (0.2, 0.6)

For three (R, T) combinations, the solution time exceeds the time limit 
when number of jobs is >= 400. 
They are : 
         (0.2, 0.6) for number of jobs = 400 
	 (0.2, 0.4) for number of jobs = 500   
	 (0.2, 0.6) for number of jobs = 500   
	 (0.2, 0.8) for number of jobs = 500