wild Card Entry

class Solution
{
    public int[] antiDiagonalPattern(int[][] mat)
    {
        // Code here
       int row = 0;

        int n = mat.length;
        int m = mat[0].length;
        int[] out = new int[n*m];
        int o = 0;
        int itr = 0;

        while (itr < n + m) {
            int col = 0;
            if (itr >= m) {
                row+=1;
                col = m - 1;
            } else col = itr;
           int frow = row;
            while (isValid(frow, col, mat)) {
                out[o++] = mat[frow][col];
               // System.out.print(mat[frow][col] + "  ");
                frow += 1;
                col -= 1;
            }

            itr += 1;
        }

       return out;

    }
    
    public static boolean isValid(int i, int j , int[][] matrix)
    {
        return (i>=0 && j>=0 && i< matrix.length && j<matrix[0].length);
    }
}