* #variable= 5 #constraint= 3
*
* comments
*
* 
min: 1*x2 -1*x3 ;
1*x1 +4*x2 -2*x5 >=2;
-1 * x1 +4 * x2 -2 * x5 >= 3;
12345678901234567890 * x4 +4 *x3 >= 10;