a,b,c,d = map(float,input().split()) if (a==b and c==d) or (a==d and b==c) or (c==a and d == b): print("YES") else: print("NO")

include <bits/stdc++.h>

using namespace std; int main() { double a , b , c , d; cin>>a>>b>>c>>d;

if(a == b and c == d)
{
    cout<<"YES";
}

else if(a == c and b == d)
{
    cout<<"YES";
}

else if(a == d and b == c)
{
    cout<<"YES";
}

else
{
    cout<<"NO";
}

}

include <bits/stdc++.h>

using namespace std; int main() { iosbase::syncwith_stdio(0); cin.tie(0); double a,b,c,d; cin>>a>>b>>c>>d; if(a==c && b==d){ cout<<"YES"; } else if(a==b && d==c){ cout<<"YES"; } else if(a==d && b==c){ cout<<"YES"; } else{ cout<<"NO"; }

     return 0;

}