greedy/container-with-most-water

Container With Most Water

描述

Given n non-negative integers $$a_1, a_2, ..., a_n$$, where each represents a point at coordinate $$(i, a_i)$$. n vertical lines are drawn such that the two endpoints of line i is at $$(i, a_i)$$ and (i, 0). Find two lines, which together with x-axis forms a container, such that the container contains the most water.

Note: You may not slant the container.

分析

每个容器的面积，取决于最短的木板。

代码

// Container With Most Water
// 时间复杂度O(n)，空间复杂度O(1)
public class Solution {
    public int maxArea(int[] height) {
        int start = 0;
        int end = height.length - 1;
        int result = Integer.MIN_VALUE;
        while (start < end) {
            int area = Math.min(height[end], height[start]) * (end - start);
            result = Math.max(result, area);
            if (height[start] <= height[end]) {
                start++;
            } else {
                end--;
            }
        }
        return result;
    }
}

// LeetCode, Container With Most Water
// 时间复杂度O(n)，空间复杂度O(1)
class Solution {
public:
    int maxArea(vector<int> &height) {
        int start = 0;
        int end = height.size() - 1;
        int result = INT_MIN;
        while (start < end) {
            int area = min(height[end], height[start]) * (end - start);
            result = max(result, area);
            if (height[start] <= height[end]) {
                start++;
            } else {
                end--;
            }
        }
        return result;
    }
};

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