num2bits5.circom

template Num2Bits5(n) {
    signal input in;
    signal output out[n];
    signal a[n];
    signal b[n];
    signal c[n];

    var lc = 0;
    var r = in;
    for (var i=0; i<n; i++) {
        out[i] <-- r % 5;
        lc += out[i]* 5**i;

        // (x-4)(x-3)(x-2)(x-1)x === 0
        a[i] <== (out[i]-4)*(out[i]-3);
        b[i] <== (out[i]-2)*(out[i]-1);
        c[i] <== a[i]*b[i];
        c[i]*out[i] === 0;

        r = r \ 5;
    }

    in === lc;
}

component main = Num2Bits5(6);