package main
import "fmt"
 
func main(){
	input := []int{0, 1, 0, 2, 1, 0, 1, 3, 2, 1, 2, 1}
	output := AnswerOfWater(input)
	fmt.Println(output)
}
 
func AnswerOfWater(values []int) int {
	sum := 0
	bucket := 1
	level := 0
	left := false
	for bucket > 0 {
		bucket = 0
		water := 0
		left = false
		for _, value := range values {
			if value - level > 0 {
				left = true
				bucket += water
				water = 0
			} else if left {
				water++
			}
		}
		sum += bucket
		level++
	}
	return sum
}

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