1598. Crawler Log Folder.cpp

// 1598. Crawler Log Folder
// Solved
// Easy
// Topics
// Companies
// Hint
// The Leetcode file system keeps a log each time some user performs a change folder operation.

// The operations are described below:

// "../" : Move to the parent folder of the current folder. (If you are already in the main folder, remain in the same folder).
// "./" : Remain in the same folder.
// "x/" : Move to the child folder named x (This folder is guaranteed to always exist).
// You are given a list of strings logs where logs[i] is the operation performed by the user at the ith step.

// The file system starts in the main folder, then the operations in logs are performed.

// Return the minimum number of operations needed to go back to the main folder after the change folder operations.

 

// Example 1:



// Input: logs = ["d1/","d2/","../","d21/","./"]
// Output: 2
// Explanation: Use this change folder operation "../" 2 times and go back to the main folder.
// Example 2:



// Input: logs = ["d1/","d2/","./","d3/","../","d31/"]
// Output: 3
// Example 3:

// Input: logs = ["d1/","../","../","../"]
// Output: 0
 

// Constraints:

// 1 <= logs.length <= 103
// 2 <= logs[i].length <= 10
// logs[i] contains lowercase English letters, digits, '.', and '/'.
// logs[i] follows the format described in the statement.
// Folder names consist of lowercase English letters and digits.

class Solution {
public:
    int minOperations(vector<string>& logs) {
        int n=0;
        if(n<0) return 0;
        for(int i=0;i<logs.size();i++){
            if(logs[i]=="../"){
               if(n>0) n--;
            }else if(logs[i]=="./"){
                continue;
            }else{
                n++;
            }
        }
        return n;
    }
};