【leetcode刷题】T178-救生艇

示例 1：
输入：people = [1,2], limit = 3
输出：1
解释：1 艘船载 (1, 2)

示例 2：
输入：people = [3,2,2,1], limit = 3
输出：3
解释：3 艘船分别载 (1, 2), (2) 和 (3)

示例 3：
输入：people = [3,5,3,4], limit = 5
输出：4
解释：4 艘船分别载 (3), (3), (4), (5)

for i in range(limit, 0, -1):
    if d.get(i, 0) == 0:
        continue
    d[i] -=1
    res += 1
    for j in range(i, 0, -1):
        if d.get(j, 0) > 0:
            d[j] -= 1
            continue

class Solution(object):
    def numRescueBoats(self, people, limit):
        """
        :type people: List[int]
        :type limit: int
        :rtype: int
        """
        people.sort()
        left, right = 0, len(people) - 1
        count = 0
        while left <= right:
            if people[left] + people[right] <= limit:
                left += 1
            right -= 1
            count += 1
        return count

class Solution {
public:
    int numRescueBoats(vector<int>& people, int limit) {
        sort(people.begin(), people.end());
        int left = 0, right = people.size() - 1;
        int count = 0;
        while(left <= right){
            if(people[left] + people[right] <= limit)
                left++;
            right--;
            count++;
        }
        return count;
    }
};