leetcode 11 -- Container With Most Water

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.

题意

从给定数组a[i]中找出 i，j使得 abs(j-i)*min(a[i],a[j])值最大

思路

刚开始使用两重循环，o(n^2)，超时；改为贪心思想，每次只尝试有可能更优的解，最终遍历完后，时间复杂度o(n);
具体步骤 设i位于序列首，j位于序列尾，则若a[i]

int maxArea(int* height, int heightSize) 
{
    int max=0,f,a,i=0,j=heightSize-1;
    while(i<j)
    {
        f=height[i]<height[j]?1:0;
        if(f)
        {
            a=(j-i)*height[i];
            i++;
        }
        else
        {
            a=(j-i)*height[j];
            j--;
        }
        if(a>max)
        {
            max=a;
        }
    }
    return max;
}