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".
这种题主要是连形状都没弄清楚，悲剧。。。
发现所有行的重复周期都是 2 * nRows - 2
对于首行和末行之间的行，还会额外重复一次，重复的这一次距离本周期起始字符的距离是 2 * nRows - 2 - 2 * i
C++代码如下：
#include<iostream> #include<string> using namespace std; class Solution { public: string convert(string s, int nRows) { // Start typing your C/C++ solution below // DO NOT write int main() function string result; if (nRows < 2) return s; for (int i = 0;i < nRows;++i) { for (int j = i;j < s.length();j += 2 * (nRows - 1)) { result.push_back(s[j]); if (i > 0 && i < nRows - 1) { if (j + 2 * (nRows - i - 1) < s.length()) result.push_back(s[j + 2 * (nRows - i - 1)]); } } } return result; } }; int main() { Solution s; string ss="PAYPALISHIRING"; string sss="0123456789"; cout<<s.convert(sss,4)<<endl; }
运行结果：
