Create Container With Most Water

Initialize l and r at the first and last location, use two points i,j. 
1. i = l + 1, j = r - 1;
2. if(height[l] < height[r]) then height[l] determine the capacity of water. so we traversal from left to find the first postion which height is higher than height[l]. update the result. change l = i; or if(height[r] <= height[l]) then height[r] determine the capacity. so we traversal from right to left to find the first postion which height is higher than height[r]. update the result and change r = j; go to 2 until i >= r or j <= l