Sequential Digits
Problem Statement - link #
An integer has sequential digits if and only if each digit in the number is one more than the previous digit.
Return a sorted list of all the integers in the range [low, high] inclusive that have sequential digits.
Examples #
Example 1:
Input: low = 100, high = 300
Output: [123,234]
Example 2:
Input: low = 1000, high = 13000
Output: [1234,2345,3456,4567,5678,6789,12345]
Constraints #
10 <= low <= high <= 10^9
Solutions #
class Solution {
public:
vector<int> ans;
void dfs(int low, int high, int i, int num){
if (num >= low and num <= high)
ans.push_back(num);
if (num > high or i>9)
return;
dfs(low, high, i+1, num*10 + i);
}
vector<int> sequentialDigits(int low, int high) {
for(int i=1; i<=9; i++)
dfs(low, high, i, 0);
sort(ans.begin(), ans.end());
return ans;
}
};