#include using namespace std; using ll = long long; #define ALL(obj) (obj).begin(),(obj).end() template using priority_queue_reverse = priority_queue,greater>; constexpr long long MOD = 1'000'000'000LL + 7; constexpr long long MOD2 = 998244353; constexpr long long HIGHINF = (long long)1e18; constexpr long long LOWINF = (long long)1e15; constexpr long double PI = 3.1415926535897932384626433L; template vector multivector(size_t N,T init){return vector(N,init);} template auto multivector(size_t N,T... t){return vector(N,multivector(t...));} template void corner(bool flg, T hoge) {if (flg) {cout << hoge << endl; exit(0);}} template ostream &operator<<(ostream &o, const map&obj) {o << "{"; for (auto &x : obj) o << " {" << x.first << " : " << x.second << "}" << ","; o << " }"; return o;} template ostream &operator<<(ostream &o, const set&obj) {o << "{"; for (auto itr = obj.begin(); itr != obj.end(); ++itr) o << (itr != obj.begin() ? ", " : "") << *itr; o << "}"; return o;} template ostream &operator<<(ostream &o, const multiset&obj) {o << "{"; for (auto itr = obj.begin(); itr != obj.end(); ++itr) o << (itr != obj.begin() ? ", " : "") << *itr; o << "}"; return o;} template ostream &operator<<(ostream &o, const vector&obj) {o << "{"; for (int i = 0; i < (int)obj.size(); ++i)o << (i > 0 ? ", " : "") << obj[i]; o << "}"; return o;} template ostream &operator<<(ostream &o, const pair&obj) {o << "{" << obj.first << ", " << obj.second << "}"; return o;} void print(void) {cout << endl;} template void print(Head&& head) {cout << head;print();} template void print(Head&& head, Tail&&... tail) {cout << head << " ";print(forward(tail)...);} template void chmax(T& a, const T b){a=max(a,b);} template void chmin(T& a, const T b){a=min(a,b);} vector split(const string &str, const char delemiter) {vector res;stringstream ss(str);string buffer; while( getline(ss, buffer, delemiter) ) res.push_back(buffer); return res;} int msb(int x) {return x?31-__builtin_clz(x):-1;} void YN(bool flg) {cout << (flg ? "YES" : "NO") << endl;} void Yn(bool flg) {cout << (flg ? "Yes" : "No") << endl;} void yn(bool flg) {cout << (flg ? "yes" : "no") << endl;} /* * @title LazySegmentTree */ template class LazySegmentTree { using TypeNode = typename Operator::TypeNode; using TypeLazy = typename Operator::TypeLazy; size_t num; size_t length; size_t height; vector node; vector lazy; vector> range; void propagate(int k) { if(lazy[k] == Operator::unit_lazy) return; node[k] = Operator::func_merge(node[k],lazy[k],range[k].second-range[k].first); if(k < length) lazy[2*k+0] = Operator::func_lazy(lazy[2*k+0],lazy[k]); if(k < length) lazy[2*k+1] = Operator::func_lazy(lazy[2*k+1],lazy[k]); lazy[k] = Operator::unit_lazy; } public: //unitで初期化 LazySegmentTree(const size_t num) : num(num) { for (length = 1,height = 0; length <= num; length *= 2, height++); node.resize(2 * length, Operator::unit_node); lazy.resize(2 * length, Operator::unit_lazy); for (int i = 0; i < num; ++i) node[i + length] = Operator::unit_node; for (int i = length - 1; i >= 0; --i) node[i] = Operator::func_node(node[(i<<1)+0],node[(i<<1)+1]); range.resize(2 * length); for (int i = 0; i < length; ++i) range[i+length] = make_pair(i,i+1); for (int i = length - 1; i >= 0; --i) range[i] = make_pair(range[(i<<1)+0].first,range[(i<<1)+1].second); } // //同じinitで初期化 LazySegmentTree(const size_t num, const TypeNode init) : num(num) { for (length = 1,height = 0; length <= num; length *= 2, height++); node.resize(2 * length, Operator::unit_node); lazy.resize(2 * length, Operator::unit_lazy); for (int i = 0; i < num; ++i) node[i + length] = init; for (int i = length - 1; i >= 0; --i) node[i] = Operator::func_node(node[(i<<1)+0],node[(i<<1)+1]); range.resize(2 * length); for (int i = 0; i < length; ++i) range[i+length] = make_pair(i,i+1); for (int i = length - 1; i >= 0; --i) range[i] = make_pair(range[(i<<1)+0].first,range[(i<<1)+1].second); } //vectorで初期化 LazySegmentTree(const vector& vec) : num(vec.size()) { for (length = 1,height = 0; length <= vec.size(); length *= 2, height++); node.resize(2 * length, Operator::unit_node); lazy.resize(2 * length, Operator::unit_lazy); for (int i = 0; i < vec.size(); ++i) node[i + length] = vec[i]; for (int i = length - 1; i >= 0; --i) node[i] = Operator::func_node(node[(i<<1)+0],node[(i<<1)+1]); range.resize(2 * length); for (int i = 0; i < length; ++i) range[i+length] = make_pair(i,i+1); for (int i = length - 1; i >= 0; --i) range[i] = make_pair(range[(i<<1)+0].first,range[(i<<1)+1].second); } //update [a,b) void update(int a, int b, TypeLazy x) { int l = a + length, r = b + length - 1; for (int i = height; 0 < i; --i) propagate(l >> i), propagate(r >> i); for(r++; l < r; l >>=1, r >>=1) { if(l&1) lazy[l] = Operator::func_lazy(lazy[l],x), propagate(l),l++; if(r&1) --r,lazy[r] = Operator::func_lazy(lazy[r],x), propagate(r); } l = a + length, r = b + length - 1; while ((l>>=1),(r>>=1),l) { if(lazy[l] == Operator::unit_lazy) node[l] = Operator::func_node(Operator::func_merge(node[(l<<1)+0],lazy[(l<<1)+0],range[(l<<1)+0].second-range[(l<<1)+0].first),Operator::func_merge(node[(l<<1)+1],lazy[(l<<1)+1],range[(l<<1)+1].second-range[(l<<1)+1].first)); if(lazy[r] == Operator::unit_lazy) node[r] = Operator::func_node(Operator::func_merge(node[(r<<1)+0],lazy[(r<<1)+0],range[(r<<1)+0].second-range[(r<<1)+0].first),Operator::func_merge(node[(r<<1)+1],lazy[(r<<1)+1],range[(r<<1)+1].second-range[(r<<1)+1].first)); } } //get [a,b) TypeNode get(int a, int b) { int l = a + length, r = b + length - 1; for (int i = height; 0 < i; --i) propagate(l >> i), propagate(r >> i); TypeNode vl = Operator::unit_node, vr = Operator::unit_node; for(r++; l < r; l >>=1, r >>=1) { if(l&1) vl = Operator::func_node(vl,Operator::func_merge(node[l],lazy[l],range[l].second-range[l].first)),l++; if(r&1) r--,vr = Operator::func_node(Operator::func_merge(node[r],lazy[r],range[r].second-range[r].first),vr); } return Operator::func_node(vl,vr); } //return [0,length] int prefix_binary_search(TypeNode var) { int l = length, r = 2*length - 1; for (int i = height; 0 < i; --i) propagate(l >> i), propagate(r >> i); if(!Operator::func_check(node[1],var)) return num; TypeNode ret = Operator::unit_node; size_t idx = 2; for(; idx < 2*length; idx<<=1){ if(!Operator::func_check(Operator::func_node(ret,Operator::func_merge(node[idx],lazy[idx],range[idx].second-range[idx].first)),var)) { ret = Operator::func_node(ret,Operator::func_merge(node[idx],lazy[idx],range[idx].second-range[idx].first)); idx++; } } return min((idx>>1) - length,num); } //range[l,r) return [l,r] int binary_search(size_t l, size_t r, TypeNode var) { if (l < 0 || length <= l || r < 0 || length < r) return -1; for (int i = height; 0 < i; --i) propagate((l+length) >> i), propagate((r+length-1) >> i); TypeNode ret = Operator::unit_node; size_t off = l; for(size_t idx = l+length; idx < 2*length && off < r; ){ if(range[idx].second<=r && !Operator::func_check(Operator::func_node(ret,Operator::func_merge(node[idx],lazy[idx],range[idx].second-range[idx].first)),var)) { ret = Operator::func_node(ret,Operator::func_merge(node[idx],lazy[idx],range[idx].second-range[idx].first)); off = range[idx++].second; if(!(idx&1)) idx >>= 1; } else{ idx <<=1; } } return off; } void print(){ // cout << "node" << endl; // for(int i = 1,j = 1; i < 2*length; ++i) { // cout << node[i] << " "; // if(i==((1< struct NodeMinRangeAdd { using TypeNode = T; using TypeLazy = U; inline static constexpr TypeNode unit_node = 1234567890; inline static constexpr TypeLazy unit_lazy = 0; inline static constexpr TypeNode func_node(TypeNode l,TypeNode r){return min(l,r);} inline static constexpr TypeLazy func_lazy(TypeLazy l,TypeLazy r){return l+r;} inline static constexpr TypeNode func_merge(TypeNode l,TypeLazy r,int len){return l+r;} // LazySegmentTree> Seg(N,0); }; //node:総和 lazy:更新 template struct NodeSumRangeUpdate { using TypeNode = T; using TypeLazy = U; inline static constexpr TypeNode unit_node = 0; inline static constexpr TypeLazy unit_lazy = -2000; inline static constexpr TypeNode func_node(TypeNode l,TypeNode r){return l+r;} inline static constexpr TypeLazy func_lazy(TypeLazy l,TypeLazy r){return r;} inline static constexpr TypeNode func_merge(TypeNode l,TypeLazy r,int len){return r!=-2000?r*len:l;} inline static constexpr bool func_check(TypeNode nodeVal,TypeNode var){return var <= nodeVal;} // LazySegmentTree> Seg(N,0); }; //node:総和 lazy:更新 template struct NodeSumRangeAdd { using TypeNode = T; using TypeLazy = U; inline static constexpr TypeNode unit_node = 0; inline static constexpr TypeLazy unit_lazy = 0; inline static constexpr TypeNode func_node(TypeNode l,TypeNode r){return l+r;} inline static constexpr TypeLazy func_lazy(TypeLazy l,TypeLazy r){return l+r;} inline static constexpr TypeNode func_merge(TypeNode l,TypeLazy r,int len){return l+r*len;} inline static constexpr bool func_check(TypeNode nodeVal,TypeNode var){return var <= nodeVal;} // LazySegmentTree> Seg(N,0); }; int main() { cin.tie(0);ios::sync_with_stdio(false); int N; cin >> N; vector A(N+1,0); for(int i = 1; i <= N; ++i) { cin >> A[i]; } for(int i = 1; i <= N; ++i) { corner(A[i]>i,"No"); } LazySegmentTree> seg(A); for(int i = N; 1 <= i; --i) { ll m = seg.get(i,i+1); corner(m%i,"No"); if(!m) continue; seg.update(0,i,m/i); } cout << "Yes" << endl; return 0; }