LeetCode 6번 ZigZag Conversion

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문제 링크

ZigZag Conversion - LeetCode

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문제

The string "PAYPALISHIRING" is written in a zigzag pattern on a given number of rows like this: (you may want to display this pattern in a fixed font for better legibility)

 

P   A   H   N
A P L S I I G
Y   I   R

 

And then read line by line: "PAHNAPLSIIGYIR"

Write the code that will take a string and make this conversion given a number of rows:

string convert(string s, int numRows);

 

Example 1:

Input: s = "PAYPALISHIRING", numRows = 3
Output: "PAHNAPLSIIGYIR"

Example 2:

Input: s = "PAYPALISHIRING", numRows = 4
Output: "PINALSIGYAHRPI"
Explanation:
P     I    N
A   L S  I G
Y A   H R
P     I

Example 3:

Input: s = "A", numRows = 1
Output: "A"

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풀이

해당 문제는 주여진 문자열을 지그재리로 배열한 후 출력하시면 됩니다.

Input: s = "ac"
Output: "a"

 

 

class Solution {
public:
	string convert(string s, int numRows)
	{
		vector<string> zigzag(numRows);
		string answer = "";
		bool isDown = true;
		for (int i = 0, j = 0; i < s.size(); i++)
		{
			zigzag[j] += s[i];
			
			if (numRows > 1)
			{
				if (i != 0 && i % (numRows - 1) == 0)
				{
					isDown = !isDown;
				}

				j += (isDown == true ? 1 : -1);
			}
		}

		for (int i = 0; i < numRows; i++)
		{
			answer += zigzag[i];
		}
		return answer;
	}
};

Time Submitted	Status	RunTime	Memory
08/03/2021 23:14	Accepted	4 ms	10.8  MB

시간 복잡도 : O(N^2)