Algorithm
Problem Name: 846. Hand of Straights
Alice has some number of cards and she wants to rearrange the cards into groups so that each group is of size groupSize, and consists of groupSize consecutive cards.
Given an integer array hand where hand[i] is the value written on the ith card and an integer groupSize, return true if she can rearrange the cards, or false otherwise.
Example 1:
Input: hand = [1,2,3,6,2,3,4,7,8], groupSize = 3 Output: true Explanation: Alice's hand can be rearranged as [1,2,3],[2,3,4],[6,7,8]
Example 2:
Input: hand = [1,2,3,4,5], groupSize = 4 Output: false Explanation: Alice's hand can not be rearranged into groups of 4.
Constraints:
1 <= hand.length <= 1040 <= hand[i] <= 1091 <= groupSize <= hand.length
Code Examples
#1 Code Example with C++ Programming
Code -
C++ Programming
class Solution {
public:
bool isNStraightHand(vector<int>& hand, int W) {
int n = hand.size();
if(n % W) return false;
map < int, int>m;
for(int x: hand) m[x]++;
auto l = m.begin();
for(int i = 0; i < n/W; i++){
auto r = l, t = m.end();
advance(r, W - 1);
for(int j = W - 1; j >= 0; j--, r--)
if((*r).second-- <= 0 || ((*r).first - (*l).first != j)) return false;
else if((*r>.second > 0) t = r;
if(t != m.end()) l = t;
else advance(l, W);
}
return true;
}
};
Input
Output
#2 Code Example with Java Programming
Code -
Java Programming
start coding...
class Solution {
public boolean isNStraightHand(int[] hand, int W) {
if (hand.length % W != 0) {
return false;
}
Map < Integer, Integer> counterMap = new HashMap<>();
Set set = new TreeSet<>();
for (int num : hand) {
counterMap.put(num, counterMap.getOrDefault(num, 0) + 1);
set.add(num);
}
Iterator < Integer> iter = set.iterator();
Integer curr = iter.next();
while (counterMap.get(curr) > 0) {
int temp = curr;
for (int i = 0; i < W; i++) {
if (counterMap.getOrDefault(temp, 0) == 0) {
return false;
}
counterMap.put(temp, counterMap.get(temp) - 1);
temp++;
}
while (iter.hasNext() && counterMap.get(curr) == 0) {
curr = iter.next();
}
}
return true;
}
}
Input
Output
#3 Code Example with Python Programming
Code -
Python Programming
class Solution:
def isNStraightHand(self, hand, W):
hand.sort()
while hand:
try:
base = hand[0]
for i in range(W):
hand.remove(base+i)
except:
return False
return True
Input
Output
#4 Code Example with C# Programming
Code -
C# Programming
using System.Collections.Generic;
using System.Linq;
namespace LeetCode
{
public class _0846_HandOfStraights
{
public bool IsNStraightHand(int[] hand, int W)
{
if (hand.Length % W != 0) return false;
var counts = new SortedDictionary < int, int>();
foreach (var num in hand)
{
if (counts.ContainsKey(num))
counts[num]++;
else
counts[num] = 1;
}
while (counts.Count > 0)
{
var start = counts.Keys.First();
for (int i = start; i < start + W; i++)
{
if (!counts.ContainsKey(i)) return false;
if (counts[i] == 1) counts.Remove(i);
else counts[i]--;
}
}
return true;
}
}
}
Input
Output