Leetcode 第6题ZigZag Conversion

题目：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”.

题目含义：

将字符按照N结果排列，然后再水平开始读最后将结果以字符串的形式返回

代码：

C++：

class Solution {
public:
string convert(string s, int numRows) {
int l=s.length();
if(numRows <= 1)
{
return s;
}
int step=2*(numRows-1);
string res="";
for(int i=0;i<numRows;i++)
{
for(int j=i;j<l;j+=step)
{
res += s[j];
if(i==0 || i==numRows-1)
{
continue;
}
int temp=j+step-2*i;
if(temp<l)
{
res+=s[j+step-2*i];
}
}
}
return res;
}
};