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*/
 19pragma circom 2.0.0;
 20
 21template MultiMux4(n) {
 22    signal input c[n][16];  // Constants
 23    signal input s[4];   // Selector
 24    signal output out[n];
 25
 26    signal a3210[n];
 27    signal a321[n];
 28    signal a320[n];
 29    signal a310[n];
 30    signal a32[n];
 31    signal a31[n];
 32    signal a30[n];
 33    signal a3[n];
 34
 35    signal a210[n];
 36    signal a21[n];
 37    signal a20[n];
 38    signal a10[n];
 39    signal a2[n];
 40    signal a1[n];
 41    signal a0[n];
 42    signal a[n];
 43
 44    // 4 constrains for the intermediary variables
 45    signal  s10;
 46    s10 <== s[1] * s[0];
 47    signal  s20;
 48    s20 <== s[2] * s[0];
 49    signal  s21;
 50    s21 <== s[2] * s[1];
 51    signal s210;
 52    s210 <==  s21 * s[0];
 53
 54
 55    for (var i=0; i<n; i++) {
 56
 57        a3210[i] <==  ( c[i][15]-c[i][14]-c[i][13]+c[i][12] - c[i][11]+c[i][10]+c[i][ 9]-c[i][ 8]
 58                       -c[i][ 7]+c[i][ 6]+c[i][ 5]-c[i][ 4] + c[i][ 3]-c[i][ 2]-c[i][ 1]+c[i][ 0] ) * s210;
 59         a321[i] <==  ( c[i][14]-c[i][12]-c[i][10]+c[i][ 8] - c[i][ 6]+c[i][ 4]+c[i][ 2]-c[i][ 0] ) * s21;
 60         a320[i] <==  ( c[i][13]-c[i][12]-c[i][ 9]+c[i][ 8] - c[i][ 5]+c[i][ 4]+c[i][ 1]-c[i][ 0] ) * s20;
 61         a310[i] <==  ( c[i][11]-c[i][10]-c[i][ 9]+c[i][ 8] - c[i][ 3]+c[i][ 2]+c[i][ 1]-c[i][ 0] ) * s10;
 62          a32[i] <==  ( c[i][12]-c[i][ 8]-c[i][ 4]+c[i][ 0] ) * s[2];
 63          a31[i] <==  ( c[i][10]-c[i][ 8]-c[i][ 2]+c[i][ 0] ) * s[1];
 64          a30[i] <==  ( c[i][ 9]-c[i][ 8]-c[i][ 1]+c[i][ 0] ) * s[0];
 65           a3[i] <==  ( c[i][ 8]-c[i][ 0] );
 66
 67         a210[i] <==  ( c[i][ 7]-c[i][ 6]-c[i][ 5]+c[i][ 4] - c[i][ 3]+c[i][ 2]+c[i][ 1]-c[i][ 0] ) * s210;
 68          a21[i] <==  ( c[i][ 6]-c[i][ 4]-c[i][ 2]+c[i][ 0] ) * s21;
 69          a20[i] <==  ( c[i][ 5]-c[i][ 4]-c[i][ 1]+c[i][ 0] ) * s20;
 70          a10[i] <==  ( c[i][ 3]-c[i][ 2]-c[i][ 1]+c[i][ 0] ) * s10;
 71           a2[i] <==  ( c[i][ 4]-c[i][ 0] ) * s[2];
 72           a1[i] <==  ( c[i][ 2]-c[i][ 0] ) * s[1];
 73           a0[i] <==  ( c[i][ 1]-c[i][ 0] ) * s[0];
 74            a[i] <==  ( c[i][ 0] );
 75
 76          out[i] <== ( a3210[i] + a321[i] + a320[i] + a310[i] + a32[i] + a31[i] + a30[i] + a3[i] ) * s[3] +
 77                     (  a210[i] +  a21[i] +  a20[i] +  a10[i] +  a2[i] +  a1[i] +  a0[i] +  a[i] );
 78
 79/*
 80        out[i] <== (  s210 * ( c[i][15]-c[i][14]-c[i][13]+c[i][12] - c[i][11]+c[i][10]+c[i][ 9]-c[i][ 8]
 81                              -c[i][ 7]+c[i][ 6]+c[i][ 5]-c[i][ 4] + c[i][ 3]-c[i][ 2]-c[i][ 1]+c[i][ 0] ) +
 82                       s21 * ( c[i][14]-c[i][12]-c[i][10]+c[i][ 8] - c[i][ 6]+c[i][ 4]+c[i][ 2]-c[i][ 0] ) +
 83                       s20 * ( c[i][13]-c[i][12]-c[i][ 9]+c[i][ 8] - c[i][ 5]+c[i][ 4]+c[i][ 1]-c[i][ 0] ) +
 84                       s10 * ( c[i][11]-c[i][10]-c[i][ 9]+c[i][ 8] - c[i][ 3]+c[i][ 2]+c[i][ 1]-c[i][ 0] ) +
 85                      s[2] * ( c[i][12]-c[i][ 8]-c[i][ 4]+c[i][ 0] ) +
 86                      s[1] * ( c[i][10]-c[i][ 8]-c[i][ 2]+c[i][ 0] ) +
 87                      s[0] * ( c[i][ 9]-c[i][ 8]-c[i][ 1]+c[i][ 0] ) +
 88                             ( c[i][ 8]-c[i][ 0] ) ) * s[3]  +
 89                (     s210 * ( c[i][ 7]-c[i][ 6]-c[i][ 5]+c[i][ 4] - c[i][ 3]+c[i][ 2]+c[i][ 1]-c[i][ 0] ) +
 90                       s21 * ( c[i][ 6]-c[i][ 4]-c[i][ 2]+c[i][ 0] ) +
 91                       s20 * ( c[i][ 5]-c[i][ 4]-c[i][ 1]+c[i][ 0] ) +
 92                       s10 * ( c[i][ 3]-c[i][ 2]-c[i][ 1]+c[i][ 0] ) +
 93                      s[2] * ( c[i][ 4]-c[i][ 0] ) +
 94                      s[1] * ( c[i][ 2]-c[i][ 0] ) +
 95                      s[0] * ( c[i][ 1]-c[i][ 0] ) +
 96                             ( c[i][ 0] ));
 97
 98*/
 99    }
100}
101
102template Mux4() {
103    var i;
104    signal input c[16];  // Constants
105    signal input s[4];   // Selector
106    signal output out;
107
108    component mux = MultiMux4(1);
109
110    for (i=0; i<16; i++) {
111        mux.c[0][i] <== c[i];
112    }
113
114    for (i=0; i<4; i++) {
115      s[i] ==> mux.s[i];
116    }
117
118    mux.out[0] ==> out;
119}