ZigZag Conversion

Posted 2020-06-24

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)

思路：

　　间距=2*numRows-2;

　　

class Solution {
public:
    string convert(string s, int numRows) {
       string ans;
        int len=s.length();
        if(numRows==1||len<=numRows)
            return s;//处理特殊情况
        for(int i=0;i<numRows;i++){
            int interval=2*(numRows-i)-2,j=i,flag=1;;
            ans.push_back(s[i]);
            while(j<len){
                if(flag){
                    i==0?flag=1:flag=0;
                    i<numRows-1?j=j+interval:j=j+2*numRows-2;
                    if(j<len)
                        ans.push_back(s[j]);
                }
                else{
                    flag=1;
                    i<numRows-1?j=j+2*i:j=j+2*numRows-2;
                    if(j<len)
                        ans.push_back(s[j]);
                }
            }
        }
        return ans;        
    }
};