A method detects a particular freeway-ramp-freeway situation in a calculated route and corrects the route by replacing the freeway-ramp-freeway situation with all-freeway segments. The method includes the steps of: establishing a calculated route to a destination; examining the calculated route to detect whether there is a first point where the calculated route exits a freeway and a second point where the calculated route enters a freeway; evaluating map data to determine whether the freeway exited and the freeway entered are the same freeway; and replacing road segments of the calculated route between the first point and the second point constituting the freeway-ramp-freeway situation with freeway segments between the first point and the second point, thereby avoiding the freeway-ramp-freeway situation.
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