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.
思路分析:这题考察双指针和贪心,左右两个指针,从两端开始,如果左边较矮,那么我们移动左边指针向右,去看能否找到更高的左“墙”,如果找到,就计算面积更新下目前的maxArea;如果右边较矮,那么我们移动右边指针向左,去看能否找到更高的右“墙”,如果找到,就计算面积更新下目前的maxArea,直到两个指针相遇,返回maxArea
AC Code
public class Solution {
public int maxArea(int[] height) {
int l, r, lh, rh, max, temp;
l = 0;
r = height.length - 1;
lh = height[l];
rh = height[r];
max = 0;
while(l < r){
temp = Math.min(lh, rh) * (r - l);
if(max < temp) {
max = temp;
}
if(lh > rh){
//move r
while(l < r && height[r] <= rh){
r--;
}
if(l < r){
rh = height[r];
}
} else {
//move l
while(l < r && height[l] <= lh){
l++;
}
if(l < r){
lh = height[l];
}
}
}
return max;
}
}