leetcode - Container With Most Water

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.

class Solution {
public:
int maxArea(std::vector<int> &height) {
int left = 0, right = height.size()-1;
int vol, maxvol = (right-left)*std::min(height[left], height[right]);
int l=left, r=right;
while(left<right){
if(height[left] <= height[right]){
while(height[++left]<=height[l] && left < right);
vol = (right-left)*std::min(height[left], height[right]);
l = left;
if(vol>maxvol){
maxvol = vol;
}
}
if(height[left] > height[right]){
while(height[--right]<=height[r]);
vol = (right-left)*std::min(height[left], height[right]);
r = right;
if(vol>maxvol){
maxvol = vol;
}
}
}
return maxvol;
}
};