Java 代码

import java.util.*;

public class Main{
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        int n = scanner.nextInt();

        while(n != 0) {
            int[] height = new int[n+1];
            for(int i = 0; i < n; i++) {
                height[i] = scanner.nextInt();
            }
            height[n] = 0;

            Deque<Rectangle> stack = new ArrayDeque<>();
            stack.push(new Rectangle(height[0], 1));
            long ans = 0;

            for(int i = 1; i <= n; i++) {
                if(stack.peek().h < height[i]) stack.push(new Rectangle(height[i], 1));
                else {
                    int width = 0;
                    while(!stack.isEmpty() && stack.peek().h >= height[i]) {
                        Rectangle rectangle = stack.pop();
                        width += rectangle.w;
                        ans = Math.max(ans, (long) rectangle.h * width);
                    }

                    stack.push( new Rectangle(height[i], width + 1) );
                }
            }

            System.out.println(ans);
            n = scanner.nextInt();
        }
    }
}

class Rectangle {
    int h, w;

    public Rectangle(int h, int w) {
        this.h = h;
        this.w = w;
    }
}