#include #include #include using namespace std; using namespace __gnu_pbds; template using treap = tree, rb_tree_tag, tree_order_statistics_node_update>; using Int = long long; #define REP(i, n) for (long long i = 0, max_i = (n); i < max_i; i++) #define REPI(i, a, b) for (long long i = (a), max_i = (b); i < max_i; i++) #define ALL(obj) begin(obj), end(obj) #define RALL(obj) rbegin(obj), rend(obj) #define fi first #define se second using ii = pair; vector dirs = { {1, 0}, {0, 1}, {-1, 0}, {0, -1}, // 4方向 {1, 1}, {-1, 1}, {-1, -1}, {1, -1}, // 斜め {0, 0}, // 自身 }; Int get_msb(long long x) { assert(x != 0); return 63 - __builtin_clzll(x); } Int get_lsb(long long x) { assert(x != 0); return __builtin_ctzll(x); } template inline bool chmax(T& a, const T& b) { if (a < b) { a = b; return true; } return false; } template inline bool chmin(T& a, const T& b) { if (a > b) { a = b; return true; } return false; } template vector make_vec(size_t n, S x) { return vector(n, x); } template auto make_vec(size_t n, Ts... ts) { return vector(ts...))>(n, make_vec(ts...)); } // debug template ostream& operator<<(ostream& s, const vector& d) { REP (i, d.size()) s << d[i] << (i == d.size() - 1 ? "" : " "); return s; } template ostream& operator<<(ostream& s, const vector>& d) { REP (i, d.size()) s << d[i] << (i == d.size() - 1 ? "" : "\n"); return s; } template ostream& operator<<(ostream& s, const pair& p) { s << "{" << p.first << ", " << p.second << "}"; return s; } template ostream& operator<<(ostream& s, const set m) { for (auto it = m.begin(); it != m.end(); it++) { s << *it << (next(it) == m.end() ? "" : "\n"); } return s; } template ostream& operator<<(ostream& s, const multiset m) { for (auto it = m.begin(); it != m.end(); it++) { s << *it << (next(it) == m.end() ? "" : "\n"); } return s; } template ostream& operator<<(ostream& s, const map m) { for (auto it = m.begin(); it != m.end(); it++) { s << *it << (next(it) == m.end() ? "" : "\n"); } return s; } template ostream& operator<<(ostream& s, const unordered_map m) { for (auto it = m.begin(); it != m.end(); it++) { s << *it << (next(it) == m.end() ? "" : "\n"); } return s; } #ifdef _MY_DEBUG #define dump(...) cerr << "/* " << #__VA_ARGS__ << " :[" << __LINE__ << ":" << __FUNCTION__ << "]" << endl, dump_func(__VA_ARGS__), cerr << "*/\n\n"; #else #define dump(...) #define endl "\n" #endif void dump_func() { cerr << endl; } template void dump_func(Head&& h, Tail&&... t) { cerr << h << (sizeof...(Tail) == 0 ? "" : ", "), dump_func(forward(t)...); } struct Fast { Fast() { cin.tie(nullptr); ios::sync_with_stdio(false); } } fast; mt19937 rnd(chrono::steady_clock::now().time_since_epoch().count()); constexpr Int MOD = 1000000007; // *************** TEMPLATE END *************** signed main() { string s; getline(cin, s); bool ok = true; REP (i, s.size()) { if (i % 2) { if (s[i] != ' ') ok = false; } else { if (s[i] == ' ') ok = false; } } cout << (ok ? "Yes" : "No") << endl; }