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.

Alt

例子:

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

思路:

暴力,复杂度$n^2$
两边缩小到中间,每次都留下比较高的那边,缩短比较矮的那边。

代码(暴力):

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class Solution {
public:
int maxArea(vector<int>& height) {
int max= 0;
int tank_h, tank_w;
for(int i = 0; i < height.size(); i++){

for(int j=i+1; j<height.size(); j++){

tank_h = height[i]>height[j]? height[j]: height[i];
tank_w = j-i;
max = tank_h*tank_w > max? tank_h*tank_w:max;

}
}
return max;
}
};

代码(两点法):