leetcode128longest consecutive sequence
given an unsorted array of integers, find the length of the longest consecutive elements sequence.
for example,
given[100, 4, 200, 1, 3, 2]
,
the longest consecutive elements sequence is[1, 2, 3, 4]
. return its length:4
.
your algorithm should run in o(n) complexity.
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我直接使用了c++的sort和unique兩個函式,先排序,然後找出重複的部分並且去除,然後再自己迴圈遍歷處理就非常簡單了。但是排序的時間複雜度貌似是nlogn,,,,我也看了網上的使用map或者set的方法,,,但是提交不通過,,,而且我自己像出來的這個方法才16ms,也不是特別慢,,,
class solution
if (nums.size() == 1)
sort(nums.begin(), nums.end());
nums.erase(unique(nums.begin(), nums.end()), nums.end());
int len = 1;
int maxlen = 1;
for (vector::iterator it = nums.begin(); it != nums.end() - 1; ++it)
else
len = 1;}}
if (len > maxlen)
maxlen = len;
return maxlen;
}};
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