When an access path continues to exist after the lifetime of the associated data object, the data object is said to be a dangling reference. An access path ordinarily leads to the location of a data object (ie., to the beginning of the block of storage for the object). At the end of the lifetime of the data object, this block of storage is recovered for real- location. However, the recovery of the storage does not necessarily destroy the existing access path to the blockithus, it may continue to exist, as a dangling reference. Storage is finite, even in large-scale machines, so a program that produces dangling references and garbage may fail to run if it exceeds the allocated memory associated with the program execution. In the following examples, we that these ustrate the situa two important issues raise during program execution Consider the following code in C language, in which x and Y as two pointer vari bles are point to ferent memory locations, as is shown in Figure 3. (a)