ex1.bash : res=1618
	time: 0:00.07 real, 0.07 user, 0.00 sys
	context-switch:	7+1, page-faults: 0+172

ex3.bash : res=548531
	time: 12:22:02 real, 44488.91 user, 2.70 sys
	context-switch:	4552388+2, page-faults: 0+98912