[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.

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Array Two Pointers

这题想明白题目之后不难，其实就是首尾指针向中间靠弄。

#include <iostream>
#include <vector>
using namespace std;

#define MIN(l,r) ((l)<(r)?(l):(r))
class Solution {
public:
int maxArea(vector<int> &height) {
int n = height.size();
if(n<2) return 0;
if(n==2)    return MIN(height[0],height[1]);
int lidx=0,ridx=n-1,sum=0;
while(lidx<ridx){
if(sum<(ridx-lidx)*MIN(height[lidx],height[ridx]))
sum = (ridx-lidx)*MIN(height[lidx],height[ridx]);
if(height[lidx]<height[ridx])
lidx++;
else
ridx--;
}
return sum;
}
};

int main()
{
vector<int > h{1,2,1};
Solution sol;
cout<<sol.maxArea(h)<<endl;
return 0;
}