[LeetCode]:ZigZag Conversion

今天开始写下LeetCode.然后按顺序搬到这里和github吧，旨在更短，更效率，同时要便于理解.

[ZigZag Conversion]

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 text, int nRows);

convert("PAYPALISHIRING", 3) should return PAHNAPLSIIGYIR.

解法：从样例中可以看出第一列就是原串中的第i个字母，然后向下跳一次，再向上跳一次，所以我们用个函数来计算每次跳动的距离，就可以得出结果。

github:https://github.com/tsfissure/LeetCode

github-this:https://github.com/tsfissure/LeetCode/tree/master/1006-ZigZag-Conversion

CPPCode:

class Solution {
public:

	static int computeMoveDistance(int iCurLine, int iNumRows, bool bIsUp) {
		return bIsUp ? iCurLine << 1 : (iNumRows - iCurLine - 1) << 1;
	}

	string convert(string s, int numRows) {
		if (numRows < 2) return s;
		string kResult = "";

		for (int i = 0; i < numRows; ++i) {
			bool bUp = false;
			for (int iMoveDis, j = i; j < (int)s.size(); j += iMoveDis, bUp ^= true) {
				iMoveDis = computeMoveDistance(i, numRows, bUp);
				if (iMoveDis > 0) kResult += s[j];
			}
		}
		return kResult;
	}
};