# LeetCode - 1954. Minimum Garden Perimeter to Collect Enough Apples
### 題目網址：https://leetcode.com/problems/minimum-garden-perimeter-to-collect-enough-apples/
###### tags: `LeetCode` `Medium` `數學`

/*
    -LeetCode format-
    Problem: 1954. Minimum Garden Perimeter to Collect Enough Apples
    Difficulty: Medium
    
    by Inversionpeter
*/



class Solution {
public:
    long long minimumPerimeter(long long neededApples) {
        int lower = 0, upper = 65536, middle;
        while (lower < upper) {
            middle = (lower + upper) >> 1;
            if ((middle << 1LL) * (middle + 1LL) * ((middle << 1LL) + 1LL) >= neededApples)
                upper = middle;
            else
                lower = middle + 1;
        }
        return lower << 3;
    }
};