LeetCode-Problems/6-Zigzag-Conversion.cpp at main · zeyadwaleed003/LeetCode-Problems · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
class Solution {
public:
    string convert(string s, int numRows) {
        if( numRows == 1 )
            return s;

        char grid[(int)1e3 + 5][(int)1e3 + 5];
        memset(grid, '/', sizeof grid);

        pair<int,int>cell = {0, 0};
        int i = 0, n = s.size();
        while( true )
        {
            if( cell.first == numRows )
            {
                cell.first -= 2;
                cell.second++;
                while( cell.first > -1 && i < n )
                    grid[cell.first--][cell.second++] = s[i++];
            }

            if( cell.first == -1 )
                cell.first += 2;

            if( i >= n )
                break;

            grid[cell.first++][cell.second] = s[i++];
        }

        string ans;
        for( int i = 0; i < 1e3 + 5; i++ )
            for( int j = 0; j < 1e3 + 5; j++ )
                if( grid[i][j] != '/' )
                    ans += grid[i][j];

        return ans;
    }
};