问题描述:
Suppose you have a random list of people standing in a queue. Each person is described by a pair of integers (h,
k)
, where h
is the height of the person and k
is
the number of people in front of this person who have a height greater than or equal to h
.
Write an algorithm to reconstruct the queue.
Note:
The number of people is less than 1,100.
示例:
Input: [[7,0], [4,4], [7,1], [5,0], [6,1], [5,2]] Output: [[5,0], [7,0], [5,2], [6,1], [4,4], [7,1]]
问题分析(这里省事了,直接摘抄英文~):
1.Pick out tallest group of people and sort them in a subarray (S). Since there's no other groups of people taller than them, therefore each guy's index will be just as same as his k value.
2.For 2nd tallest group (and the rest), insert each one of them into (S) by k value. So on and so forth.
过程详见代码:
class Solution {
public:
vector<pair<int, int>> reconstructQueue(vector<pair<int, int>>& people) {
auto com = [](const pair<int, int>& p1, const pair<int, int>& p2)
{return p1.first > p2.first || (p1.first == p2.first && p1.second < p2.second);};
sort(people.begin(), people.end(), com);
vector<pair<int, int>> res;
for (auto p : people)
{
res.insert(res.begin() + p.second, p);
}
return res;
}
};