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".
string convert(string s, int nRows) { if(nRows <= 1) return s; string result; if(s.size() ==0) return result; for(int i =0; i< nRows; i++) { for(int j =0, index =i; index < s.size(); j++, index = (2*nRows-2)*j +i) { result.append(1, s[index]); if(i ==0 || i == nRows-1) { continue; } if(index+(nRows- i-1)*2 < s.size()) { result.append(1, s[index+(nRows- i-1)*2]); } } } return result; }
原文：http://www.cnblogs.com/hexhxy/p/4797834.html