题目描述
Given a binary string S . Perform R iterations on string S, where in each iteration 0 becomes 01 and 1 becomes 10. Find the Nth character (considering 0 based indexing) of the string after performing these R iterations. (See Examples for better understanding)
Example 1:
Input:
S = 101
R = 2
N = 3
Output:
1
Explanation :
After 1st iteration S becomes 100110.
After 2nd iteration, S = 100101101001
Now, we can clearly see that the character
at 3rd index is 1, and so the output.
Example
Input:
S = 11
R = 1
N = 3
Output:
0
Explanation:
After 1st iteration S becomes 1010.
Now, we can clearly see that the character
at 3rd index is 0, and so the output.
Your task:
You don't need to read input or print anything. Your task is to complete the function nthCharacter() which takes the string S and integers R and N as input parameters and returns the N-th character of the string after performing R operations on S.
Expected Time Complexity: O(r*len(s))
Expected Auxilary Space: O(len(s))
Constraints:
1 ≤ String length ≤ 10^{3}
1 ≤ R ≤ 20
0 ≤ N < Length of final string
输入格式
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输出格式
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