ZigZag-LeetCode

题目：

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".

Zigzag:即循环对角结构.

向下循环:nRows

斜角线循环

重复...

#include <string>
#include <iostream>
using namespace std;

string convert(string s,int nRows){
     if(nRows==1) return s;
         
         string res[nRows];
         int i==0,j,gap=nRows-2;
         
         while(i<s.size()){
               for(j=0;j<nRows && i<s.size();j++) res[j]+=s[i++];
               for(j=gap;j>0 && i<s.size();j--) res[j]+=s[i++];
         }
         
         string ret="";
         for(i=0;i<nRows;i++){
             ret+=res[i];
         }
         return ret;
}