//#include #include using namespace std; typedef long long ll; typedef pair p; const ll INF = 1e9; const ll LINF = ll(1e18); const ll MOD = 1000000007; const ll dx[4] = {0, 1, 0, -1}, dy[4] = {-1, 0, 1, 0}; const ll Dx[8] = {0, 1, 1, 1, 0, -1, -1, -1}, Dy[8] = {-1, -1, 0, 1, 1, 1, 0, -1}; #define yes cout << "Yes" << endl #define YES cout << "YES" << endl #define no cout << "No" << endl #define NO cout << "NO" << endl #define rep(i, n) for (ll i = 0; i < n; i++) #define ALL(v) v.begin(), v.end() #define debug(v) \ cout << #v << ":"; \ for (auto x : v) \ { \ cout << x << ' '; \ } \ cout << endl; template bool chmax(T &a, const T &b) { if (a < b) { a = b; return 1; } return 0; } template bool chmin(T &a, const T &b) { if (b < a) { a = b; return 1; } return 0; } //cout<> n; vector a(n); rep(i, n) cin >> a[i]; reverse(ALL(a)); ll count = 0; rep(i, n) { if ((a[i] + count) % (n - i) == 0) { ll add = (a[i] + count) / (n - i); count += add; } else { no; return 0; } } yes; }