Java | Leetcode Java题解之第440题字典序的第K小数字

题目：

题解：

class Solution {public int findKthNumber(int n, int k) {int curr = 1;k--;while (k > 0) {int steps = getSteps(curr, n);if (steps <= k) {k -= steps;curr++;} else {curr = curr * 10;k--;}}return curr;}public int getSteps(int curr, long n) {int steps = 0;long first = curr;long last = curr;while (first <= n) {steps += Math.min(last, n) - first + 1;first = first * 10;last = last * 10 + 9;}return steps;}
}