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DI String Match - Math - Easy - LeetCode - MiniTV

DI String Match - Math - Easy - LeetCode - मिनी टीवी

Given a string S that only contains "I" (increase) or "D" (decrease), let N = S.length.

Return any permutation A of [0, 1, ..., N] such that for all i = 0, ..., N-1:

If S[i] == "I", then A[i] < A[i+1]
If S[i] == "D", then A[i] > A[i+1]
 

Example 1:

Input: "IDID"
Output: [0,4,1,3,2]
Example 2:

Input: "III"
Output: [0,1,2,3]
Example 3:

Input: "DDI"
Output: [3,2,0,1]
 

Note:

1 <= S.length <= 10000
S only contains characters "I" or "D".

public class Solution {
    public int[] DiStringMatch(string S) {
        int left = 0;
        int right = S.Length;
        var result = new int[S.Length+1];
        for(int i=0;i<S.Length;i++){
            if(S[i]=='I'){
                result[i]=left++;
            }
            else{
                result[i]=right--;
            }            
        }
        result[S.Length]=left;
        return result;
    }
}

Time Complexity: O(n)

Space Complexity: O(1)