Reorder Data In Log Files Problem


Description

LeetCode Problem 937.

You are given an array of logs. Each log is a space-delimited string of words, where the first word is the identifier.

There are two types of logs:

  • Letter-logs: All words (except the identifier) consist of lowercase English letters.
  • Digit-logs: All words (except the identifier) consist of digits.

Reorder these logs so that:

  • The letter-logs come before all digit-logs.
  • The letter-logs are sorted lexicographically by their contents. If their contents are the same, then sort them lexicographically by their identifiers.
  • The digit-logs maintain their relative ordering.

Return the final order of the logs.

Example 1:

1
2
3
4
5
Input: logs = ["dig1 8 1 5 1","let1 art can","dig2 3 6","let2 own kit dig","let3 art zero"]
Output: ["let1 art can","let3 art zero","let2 own kit dig","dig1 8 1 5 1","dig2 3 6"]
Explanation:
The letter-log contents are all different, so their ordering is "art can", "art zero", "own kit dig".
The digit-logs have a relative order of "dig1 8 1 5 1", "dig2 3 6".

Example 2:

1
2
Input: logs = ["a1 9 2 3 1","g1 act car","zo4 4 7","ab1 off key dog","a8 act zoo"]
Output: ["g1 act car","a8 act zoo","ab1 off key dog","a1 9 2 3 1","zo4 4 7"]

Constraints:

  • 1 <= logs.length <= 100
  • 3 <= logs[i].length <= 100
  • All the tokens of logs[i] are separated by a single space.
  • logs[i] is guaranteed to have an identifier and at least one word after the identifier.


Sample C++ Code

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
class Solution {
public:
    vector<string> reorderLogFiles(vector<string>& logs) {
        vector<string> digitLogs, ans;
        vector<pair<string, string>> letterLogs;
        for (string &s : logs) {
            int i = 0;
            while (s[i] != ' ') 
                ++i;
            if (isalpha(s[i + 1])) 
                letterLogs.emplace_back(s.substr(0, i), s.substr(i + 1));
            else 
                digitLogs.push_back(s);
        }
        sort(letterLogs.begin(), letterLogs.end(), [&](auto& a, auto& b) {
            return a.second == b.second ? a.first < b.first : a.second < b.second;
        });
        for (auto &p : letterLogs) 
            ans.push_back(p.first + " " + p.second);
        for (string &s : digitLogs) 
            ans.push_back(s);
        return ans;
    }
};




Related Posts

Sum Of Subsequence Widths Problem

LeetCode 891. The width of a sequence is the difference...

Sort An Array Problem

LeetCode 912. Given an array of integers nums, sort the...

Smallest Range II Problem

LeetCode 910. You are given an integer array nums and...

Reordered Power Of 2 Problem

LeetCode 869. You are given an integer n. We reorder...

Reorder Data In Log Files Problem

LeetCode 937. You are given an array of logs. Each...

Minimum Increment To Make Array Unique Problem

LeetCode 945. You are given an integer array nums. In...