11.container-with-most-water.cpp

/*
 * @lc app=leetcode id=11 lang=cpp
 *
 * [11] Container With Most Water
 *
 * https://leetcode.com/problems/container-with-most-water/description/
 *
 * algorithms
 * Medium (52.07%)
 * Likes:    8381
 * Dislikes: 660
 * Total Accepted:    847.1K
 * Total Submissions: 1.6M
 * Testcase Example:  '[1,8,6,2,5,4,8,3,7]'
 *
 * Given n non-negative integers a1, a2, ..., an , where each represents a
 * point at coordinate (i, ai). n vertical lines are drawn such that the two
 * endpoints of the line i is at (i, ai) and (i, 0). Find two lines, which,
 * together with the x-axis forms a container, such that the container contains
 * the most water.
 * 
 * Notice that you may not slant the container.
 * 
 * 
 * Example 1:
 * 
 * 
 * Input: height = [1,8,6,2,5,4,8,3,7]
 * Output: 49
 * Explanation: The above vertical lines are represented by array
 * [1,8,6,2,5,4,8,3,7]. In this case, the max area of water (blue section) the
 * container can contain is 49.
 * 
 * 
 * Example 2:
 * 
 * 
 * Input: height = [1,1]
 * Output: 1
 * 
 * 
 * Example 3:
 * 
 * 
 * Input: height = [4,3,2,1,4]
 * Output: 16
 * 
 * 
 * Example 4:
 * 
 * 
 * Input: height = [1,2,1]
 * Output: 2
 * 
 * 
 * 
 * Constraints:
 * 
 * 
 * n == height.length
 * 2 <= n <= 3 * 10^4
 * 0 <= height[i] <= 3 * 10^4
 * 
 * 
 */

// @lc code=start
class Solution {
public:
     int maxArea(vector<int>& height) {
        int maxResult = 0;
        int left = 0, right = height.size() - 1;
        while (left < right) {
            maxResult = max(maxResult, (right - left) * min(height[left], height[right]));
            if (height[left] < height[right])
                ++left;
            else 
                --right;
        }
        return maxResult;
    }
};
// @lc code=end