题目：

题解：

func findNthDigit(n int) int {d := 1for count := 9; n > d*count; count *= 10 {n -= d * countd++}index := n - 1start := int(math.Pow10(d - 1))num := start + index/ddigitIndex := index % dreturn num / int(math.Pow10(d-digitIndex-1)) % 10
}