1template Internal() {
 2    signal input in;
 3    signal output out;
 4
 5    out <== in;
 6}
 7
 8template InOut() {
 9    signal input in;
10    signal output out;
11
12    component internal = Internal();
13
14    internal.in <== in;
15    internal.out ==> out;
16}
17
18component main = InOut();