#include <bits/stdc++.h>
using namespace std;
int main ()
{
long long x,c=0,o=1,i=0,y;
cin >>x;
cin >>y;
while (o<y)
{
o++;
c++;
}
while (c<x)
{
c+=2;
}
if((c==x)&&(o==y))
cout <<"Yes";
else
cout <<"No";

return 0;}