[leetcode]LeetCode刷题的日子--Container With Most Water

题目

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 line i is at (i, ai) 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 and n is at least 2.

Example:

Input: [1,8,6,2,5,4,8,3,7]
Output: 49

题目翻译

给定 n 个非负整数 a1，a2，…，an，每个数代表坐标中的一个点 (i, ai) 。画 n 条垂直线，使得垂直线 i 的两个端点分别为 (i, ai) 和 (i, 0)。找出其中的两条线，使得它们与 x 轴共同构成的容器可以容纳最多的水。

解题思路

从两边同时开始遍历，一直到中间位置，找出最大的范围。注意在移动时，保证位置高不动，只移动位置低的

代码

fn max_area(height: Vec<i32>) -> i32 {
    let mut max = 0;
    let mut left = 0;
    let mut right = height.len() - 1;

    while left < right {
        let len = (right - left) as i32;
        let h = height[left].min(height[right]);

        max = max.max((len * h) as i32);

        if height[left] > height[right] {
            right -= 1;
        } else {
            left += 1
        }
    }

    return max;
}

#[test]
fn test_max_area() {
    let demo = vec![1,8,6,2,5,4,8,3,7];
    assert_eq!(max_area(demo), 49);
}