public void allPossibleWords(char C[][], int i, int j, int N, int M, char res[], int idx) {

        if (i > N || j > M) {
            return;
        }

        res[idx] = C[i][j];
        for (int l = 0; l <= idx; l++) {
            System.out.print(res[l]);
        }
        System.out.println();
        allPossibleWords(C, i + 1, j, N, M, res, idx + 1);
        allPossibleWords(C, i, j + 1, N, M, res, idx + 1);
        allPossibleWords(C, i + 1, j + 1, N, M, res, idx + 1);

    }