#include <bits/stdc++.h>
using namespace std;
//#include <atcoder/all>
//using namespace atcoder;
//using mint = modint998244353;
//using mint = modint1000000007;
typedef long long ll;
typedef unsigned long long ull;
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
const int MAX = 1e9;
const int MIN = -1*1e9;
const ll MAXLL = 1e18;
const ll MINLL = -1*1e18;
//const ll MOD = 998244353;
//const ll MOD = 1000000007;

int main()
{
    string A,B,C; cin >> A >> B >> C;
    int Ans = 0;
    if(A[0] == '-') Ans++;
    if(B[0] == '-') Ans++;
    if(C[0] == '-') Ans++;
    cout << (Ans%2==0?"Yes":"No") << endl;
}