This method can be used to minimize a collection's memory overhead if no new elements will be added to the collection. The cost of reallocating and copying a large DequeT can be considerable, however, so the TrimExcess method does nothing if the list is at more than 90 percent of capacity. This avoids incurring a large reallocation cost for a relatively small gain.

This method is an O(n) operation, where n is Count.

To reset a DequeT to its initial state, call the Clear method before calling TrimExcess method. Trimming an empty DequeT sets the capacity of the DequeT to the default capacity.

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