u,v = map(int,input().split())
if(u > v): print(-1)
elif (v-u)%2 == 1: print(-1)
else:
x = (v-u)//2
if(v == 0 and u == 0):
print(0)
elif(v == u):
print(1)
print(u)
elif(x^u) == x+u:
print(2)
print(x+u,x)
else:
print(3)
print(x,x,u)#include<bits/stdc++.h>
#define MOD 1000000007
#define MAX 200000
using namespace std;
int main()
{
ios_base::sync_with_stdio(false);
cin.tie(NULL);
long long xr, sm;
cin>>xr>>sm;
if(xr>sm)
cout<<"-1"<<endl;
else if(xr==sm)
{
if(sm)
cout<<"1"<<endl<<xr<<endl;
else cout<<"0"<<endl;
}
else if((sm-xr)%2==0)
{
//sm = a+b
//xr = a^b
//sm=xr+2(a&b) -> (sm-xr)/2 = a&b
long long ab = (sm-xr)/2,a=0,b=0;
for(int i=0;i<62;++i)
{
if(ab&((1LL)<<i))
{
a |= ((1LL)<<i);
b |= ((1LL)<<i);
}
if(xr&((1LL)<<i))
a |= ((1LL)<<i);
}
if((a^b)==xr&&(a+b)==sm)
{
cout<<"2"<<endl;
cout<<a<<" "<<b<<endl;
}
else
{
cout<<"3"<<endl;
cout<<xr<<" "<<ab<<" "<<ab<<endl;
}
}
else
{
cout<<"-1"<<endl;
}
return 0;
}
1452A - Robot Program | 344A - Magnets |
96A - Football | 702B - Powers of Two |
1036A - Function Height | 443A - Anton and Letters |
1478B - Nezzar and Lucky Number | 228A - Is your horseshoe on the other hoof |
122A - Lucky Division | 1611C - Polycarp Recovers the Permutation |
432A - Choosing Teams | 758A - Holiday Of Equality |
1650C - Weight of the System of Nested Segments | 1097A - Gennady and a Card Game |
248A - Cupboards | 1641A - Great Sequence |
1537A - Arithmetic Array | 1370A - Maximum GCD |
149A - Business trip | 34A - Reconnaissance 2 |
59A - Word | 462B - Appleman and Card Game |
1560C - Infinity Table | 1605C - Dominant Character |
1399A - Remove Smallest | 208A - Dubstep |
1581A - CQXYM Count Permutations | 337A - Puzzles |
495A - Digital Counter | 796A - Buying A House |