Have two data their variables name and layout are exactly the same

```
data data1;
input var$ val1 val2 val;
datalines;
A 0 8 8
B 9 8 7
C 7 2 3
;
data data2;
input var$ val1 val2 val;
datalines;
A 0 7 8
B 9 8 7
C 5 2 3
;
```

Want the math diff in each numeric cell.Look for elegant and smart ways. The really data set has more variables and columns.

```
data want;
input var$ val1 val2 val;
datalines;
A 0 1 0
B 0 0 0
C 2 0 0
;
```