Description Link to heading

2347. Best Poker Hand (Easy)

You are given an integer array ranks and a character array suits. You have 5 cards where the ith card has a rank of ranks[i] and a suit of suits[i]. The following are the types of poker hands you can make from best to worst:

  1. "Flush": Five cards of the same suit.
  2. "Three of a Kind": Three cards of the same rank.
  3. "Pair": Two cards of the same rank.
  4. "High Card": Any single card. Return a string representing the best type of poker hand you can make with the given cards. Note that the return values are case-sensitive. Example 1:
Input: ranks = [13,2,3,1,9], suits = ["a","a","a","a","a"]
Output: "Flush"
Explanation: The hand with all the cards consists of 5 cards with the same suit, so we have a
"Flush".

Example 2:

Input: ranks = [4,4,2,4,4], suits = ["d","a","a","b","c"]
Output: "Three of a Kind"
Explanation: The hand with the first, second, and fourth card consists of 3 cards with the same
rank, so we have a "Three of a Kind".
Note that we could also make a "Pair" hand but "Three of a Kind" is a better hand.
Also note that other cards could be used to make the "Three of a Kind" hand.

Example 3:

Input: ranks = [10,10,2,12,9], suits = ["a","b","c","a","d"]
Output: "Pair"
Explanation: The hand with the first and second card consists of 2 cards with the same rank, so we
have a "Pair".
Note that we cannot make a "Flush" or a "Three of a Kind".

Constraints:

  • ranks.length == suits.length == 5
  • 1 <= ranks[i] <= 13
  • 'a' <= suits[i] <= 'd'
  • No two cards have the same rank and suit.

Solution Link to heading

Just use two arrays as two hash table.

Code Link to heading 

class Solution {
  public:
    string bestHand(vector<int> &ranks, vector<char> &suits) {
        vector<int> color(4, 0);
        vector<int> number(14, 0);
        for (int i = 0; i < 5; i++) {
            color[suits[i] - 'a']++;
            if (color[suits[i] - 'a'] == 5)
                return "Flush";
            number[ranks[i]]++;
        }
        int maxnum = 0;
        for (int i = 1; i <= 13; i++) {
            maxnum = std::max(maxnum, number[i]);
        }
        if (maxnum >= 3)
            return "Three of a Kind";
        if (maxnum == 2)
            return "Pair";
        return "High Card";
    }
};