Given string str of length N. The task is to find the minimum characters to be added at the front to make string palindrome.
Note: A palindrome is a word which reads the same backward as forward. Example: "madam".
Example 1:
Input:
S = "abc"
Output: 2
Explanation:
Add 'b' and 'c' at front of above string to make it
palindrome : "cbabc"
Example 2:
Input:
S = "aacecaaa"
Output: 1
Explanation: Add 'a' at front of above string
to make it palindrome : "aaacecaaa"
Your Task:
You don't need to read input or print anything. Your task is to complete the function minChar() which takes a string S and returns an integer as output.
Expected Time Complexity: O(N)
Expected Auxiliary Space: O(N)
Constraints:
1 <= S.length <= 10^{6}

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