# Model file for oil refinery problem (Problem 1.16 from BT-ILO Pages 37-38)

set Products;	# gas, heating oil
set Crudes;	# Crudes A, B
param n_Proc;   # No. of processes = 3

param SellPrice {Products};
param CrudeProcess {Crudes, 1..n_Proc};   # matrix of coefficients for crudes v/s processes
param ProdProcess {Products, 1..n_Proc};  # matrix of coefficients for products v/s processes
param Cost {1..n_Proc};			  # cost per process
param CrudeReserves {Crudes};

var x {1..n_Proc} >= 0; # x[i] = # times process i is run

maximize Revenue: sum {i in Products} ( SellPrice[i]*(sum {j in 1..n_Proc} ProdProcess[i,j]*x[j]) ) 
	 	   - sum {j in 1..n_Proc} Cost[j]*x[j];

subject to MeetReservers {i in Crudes}: sum {j in 1..n_Proc} CrudeProcess[i,j]*x[j] <= CrudeReserves[i];