Shreya Raj
Reputation: 21
why is less<T> comparator used for max heap and greater<T> for min heap?
Shouldn't it be the opposite? what do we mean by less and greater in detail when we use them as comparators I don't understand the complete explanation for this, could someone please help me out.
Upvotes: 2
Views: 377
Answers (1)
463035818_is_not_an_ai
Reputation: 122133
It is purley a matter of convention to use the comparator to decide whether one element a comes before another element b. Thats why for increasing order a < b or std::less is used and for decreasing order a > b / std::greater.
If the convention was the opposite: Use the comparater to decide which element comes last. Then < would result in decreasing order and > would result in increasing order.
Upvotes: 1
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