# 0967. Numbers With Same Consecutive Differences
###### tags: `Leetcode` `Medium` `Microsoft` `Backtracking`
Link: https://leetcode.com/problems/numbers-with-same-consecutive-differences/
## 思路
典型dfs backtracking
## Code

class Solution {
    public int[] numsSameConsecDiff(int n, int k) {
        List<Integer> ans = new ArrayList<>();
        for(int i = 1;i <= 9;i++){
            dfs(ans, n-1, k, i, i);
        }
        
        int[] res = new int[ans.size()];
        for(int i = 0;i < res.length;i++){
            res[i]=ans.get(i);
        }
        return res;
    }
    private void dfs(List<Integer> ans, int n, int k, int cur, int last){
        if(n==0){
            ans.add(cur);
            return;
        }
        if(last+k<10){
            dfs(ans, n-1, k, 10*cur+last+k, last+k);
        }
        if(last-k>=0 && k!=0){
            dfs(ans, n-1, k, 10*cur+last-k, last-k);
        }
    }
}