y  material   operator  formulation
24   1          1          A
17   2          1          B
18   3          1          C
26   4          1          D
22   5          1          E
20   1          2          B
24   2          2          C
38   3          2          D
31   4          2          E
30   5          2          A
19   1          3          C    
30   2          3          D
26   3          3          E
26   4          3          A
20   5          3          B
24   1          4          D
27   2          4          E
27   3          4          A
23   4          4          B
29   5          4          C
24   1          5          E
36   2          5          A
21   3          5          B
22   4          5          C
31   5          5          D