1/*
 2    Copyright 2018 0KIMS association.
 3
 4    This file is part of circom (Zero Knowledge Circuit Compiler).
 5
 6    circom is a free software: you can redistribute it and/or modify it
 7    under the terms of the GNU General Public License as published by
 8    the Free Software Foundation, either version 3 of the License, or
 9    (at your option) any later version.
10
11    circom is distributed in the hope that it will be useful, but WITHOUT
12    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
13    or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
14    License for more details.
15
16    You should have received a copy of the GNU General Public License
17    along with circom. If not, see <https://www.gnu.org/licenses/>.
18*/
19
20template MultiMux2(n) {
21    signal input c[n][4];  // Constants
22    signal input s[2];   // Selector
23    signal output out[n];
24
25    signal a10[n];
26    signal a1[n];
27    signal a0[n];
28    signal a[n];
29
30    signal  s10;
31    s10 <== s[1] * s[0];
32
33    for (var i=0; i<n; i++) {
34
35          a10[i] <==  ( c[i][ 3]-c[i][ 2]-c[i][ 1]+c[i][ 0] ) * s10;
36           a1[i] <==  ( c[i][ 2]-c[i][ 0] ) * s[1];
37           a0[i] <==  ( c[i][ 1]-c[i][ 0] ) * s[0];
38            a[i] <==  ( c[i][ 0] )
39
40          out[i] <==  (  a10[i] +  a1[i] +  a0[i] +  a[i] );
41
42    }
43}
44
45template Mux2() {
46    var i;
47    signal input c[4];  // Constants
48    signal input s[2];   // Selector
49    signal output out;
50
51    component mux = MultiMux2(1);
52
53    for (i=0; i<4; i++) {
54        mux.c[0][i] <== c[i];
55    }
56
57    for (i=0; i<2; i++) {
58      s[i] ==> mux.s[i];
59    }
60
61    mux.out[0] ==> out;
62}