slots.qrt

#from data:stack import *

def Box box(st Int, hgt Int, wdt Int)

def [st Int, hgt Int] .box [pos Int] Box { closed(st, hgt, pos - o:st) }

def area[box Box] Int { box:hgt * box:wdt }

def [a Box] > [b Box] Bool { area[a] > area[b] }


def bestBox[slots Array[Int]] Box {
	let stack Stack[Int, Int] = newStack[]
	let biggest = box(0,0,0)
	forEach[slots] {[pos, slot]
		let h = stack.top:hgt
		if stack.isEmpty || slot > h {
			stack.push[pos, slot]
		} else {
			while {h > slot} {
				let o = stack.pop
				set biggest = max[biggest, o.box[pos]]
			}
		} 
	}
	biggest
}


let input Array[Int] = arrayOf[2, 3, 0, 5, 1, 1, 2, 1,
			                 2, 2, 1, 4, 3, 2, 1, 1,
				             6, 4, 4, 4, 5, 5, 4, 4,
				             2, 2, 2, 0, 2, 3, 0, 0]
assert[bestBox[input] = box(16, 4, 8)]