https://leetcode.com/problems/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"
.
class Solution {
public:
string convert(string s, int numRows) {
if(numRows == 1)return s;
string* a = new string[numRows];
string ans;
int n = 2 * numRows - 2;
for(int i = 0;i < s.size();i++)
{
int r = i % n;
int l = r % numRows;
if(l == r)a[l] += s[i];
else a[numRows - l - 2] += s[i];
}
for(int i = 0;i < numRows;i++){
ans += a[i];
}
return ans;
}
};