题目：原题链接（中等）
标签：哈希表、贪心算法
| 解法 | 时间复杂度 | 空间复杂度 | 执行用时 |
|---|---|---|---|
| Ans 1 (Python) | O ( N ) O(N) O(N) | O ( N ) O(N) O(N) | 520ms (20.76%) |
| Ans 2 (Python) | |||
| Ans 3 (Python) |
解法一：
class Solution:
def restoreArray(self, adjacentPairs: List[List[int]]) -> List[int]:
near = defaultdict(set)
count = Counter()
for n1, n2 in adjacentPairs:
near[n1].add(n2)
near[n2].add(n1)
count[n1] += 1
count[n2] += 1
start = 0
for num in count:
if count[num] == 1:
start = num
break
ans = [start]
while near[ans[-1]]:
now = ans[-1]
nxt = near[now].pop()
near[nxt].remove(now)
ans.append(nxt)
return ans
