If all the persons sit alphabetically from left to right than how many persons are remain unchanged ........

There are eight persons A, B, C, D, E, F, G and H sitting in a row but not necessary in the same order. Three of them facing south while remaining five are facing north. Two person sits between F and G. Both F and G are facing the same direction. Neither A nor E is an immediate neighbor of F. E faces south direction. Persons sitting at extreme ends face same direction. Not more than two adjacent persons faces same direction. H is not the neighbor of F and B. H and G faces opposite direction. Immediate neighbor of F faces opposite directions. B sits second to the right of D. One person sits between A and E. Immediate neighbor of E faces same directions. F sits third to the left of C who sits at one of the extreme end of the row.