Hand of Straights - Solution & Explanation

We can sort the array first and then use a greedy approach to construct consecutive groups of the given group size:

• Sort the cards.
• Use a frequency counter (like a dictionary or hashmap) to track the occurrences of each card.
• For each card in the sorted order, if the frequency of the card is greater than 0, attempt to form a consecutive sequence starting with this card.
• Reduce the frequency of each card in the sequence by one.
• If it is not possible to form such a sequence, return false.
• If all sequences are formed successfully, return true.

This Python code first uses a Counter to count occurrences of each card. It then attempts to form groups starting from the smallest card available, reducing counts appropriately.

This approach uses a multiset (or similar structure) to represent the occurrence of each card. It uses a similar greedy process as Approach 1 but leverages enhanced data structures for efficient access:

• Use a data structure that allows you to efficiently find, insert, and delete elements while maintaining sorted order.
• Iterate over the cards using this structure, forming groups as you go.
• Use efficient deletion/insertion operations to manage the counts of cards.

This C++ solution uses a map (similar to a multiset here) to maintain count of each card and iterates with greedy logic to form groups by decreasing the count of cards as it goes.