C++学习（4）

LeetCode 2.1.6

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

#include<map>
#include<vector>

#include<iostream>

class Solution {
	public:
			int longestConsecutive(const vector<int>& nums) {
				int length = 1;
				int longest = 0;
				for(int i = 0;i < nums.size();i++){
					if((nums[i+1]) == (nums[i] + 1)){
						++ length;
						if(length > longest)
								longest = length;
					}
					else
						length = 1;
				}
				return longest;
			}
};


int main(){
	Solution solution;
	int a[16] = {1,2,3,3,4,5,6,7,8,5,6,7,8,9,10,11};
	vector<int> va(a,a+16);
	cout<<endl;
	for(vector<int>::iterator it = va.begin();it != va.end();++it)
		cout<<*it<<" ";
	cout<<endl;
	int c = solution.longestConsecutive(va);
	cout<<c<<endl;
	return 0;
	
}

运行后：

1 2 3 3 4 5 6 7 8 5 6 7 8 9 10 11 
7