leetcode:11. Container With Most Water

描述

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.

思路

思路一：遍历+减枝

思路二：按照x轴距离最大的开始，慢慢往下缩小

代码

public class Solution {
public int maxArea(int[] height) {
int maxArea = 0;
int i = 0, j = height.length - 1;

while(i < j){
int bufArea = (height[i] > height[j] ? height[j] : height[i]) * (j - i);

maxArea = maxArea>bufArea? maxArea:bufArea;

if(height[i] < height[j])
i++;
else
j--;
}
return maxArea;
}
}

结果

他山之玉

C++ solutioin

int maxArea(vector<int>& height) {
int water = 0;
int i = 0, j = height.size() - 1;
while (i < j) {
int h = min(height[i], height[j]);
water = max(water, (j - i) * h);
while (height[i] <= h && i < j) i++;
while (height[j] <= h && i < j) j--;
}
return water;
}

Java solution

public int maxArea(int[] height) {
int left = 0, right = height.length - 1;
int maxArea = 0;

while (left < right) {
maxArea = Math.max(maxArea, Math.min(height[left], height[right])
* (right - left));
if (height[left] < height[right])
left++;
else
right--;
}

return maxArea;
}