#include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include using namespace std; typedef int64_t i64; typedef double db; typedef vector> mat; typedef pair pii; typedef pair pli; typedef pair pdi; #define esc(x) cout << (x) << endl,exit(0) #define inf(T) (numeric_limits::max() / 2 - 1) #define each(i,v) for(auto i = begin(v); i != end(v); ++i) #define reach(i,v) for(auto i = rbegin(v); i != rend(v); ++i) #define urep(i,s,t) for(int64_t i = (s); i <= (t); ++i) #define drep(i,s,t) for(int64_t i = (s); i >= (t); --i) #define rep(i,n) urep(i,0,(n) - 1) #define rep1(i,n) urep(i,1,(n)) #define rrep(i,n) drep(i,(n) - 1,0) #define all(v) begin(v),end(v) #define rall(v) rbegin(v),rend(v) #define vct vector #define prque priority_queue #define u_map unordered_map #define u_set unordered_set #define l_bnd lower_bound #define u_bnd upper_bound #define rsz resize #define ers erase #define emp emplace #define emf emplace_front #define emb emplace_back #define pof pop_front #define pob pop_back #define mkp make_pair #define mkt make_tuple #define fir first #define sec second struct setupper { setupper(uint8_t prec) { cin.tie(0); ios::sync_with_stdio(false); cout << fixed << setprecision(prec); #ifdef Local #define debug 1 #define print(x) cout << #x << " = " << (x) << " (L" << __LINE__ << ")" << endl cout << "-- Execution At Local ---\n" << "\n\n\n"; auto print_atexit = []() { time_t end_time = time(NULL); struct tm *ret = localtime(&end_time); cout << "\n----------------\n"; cout << "\nSuccessfully Executed At " << (ret -> tm_hour) << ":" << (ret -> tm_min) << ":" << (ret -> tm_sec) << "\n\n"; }; atexit(print_atexit); #endif } } setupper_obj(10); template ostream& operator << (ostream &s, pair p) { return s << p.fir << " " << p.sec; } template ostream& operator << (ostream &s, vector &v) { for(auto i = v.begin(); i != v.end(); ++i) { if(i != begin(v)) s << " "; s << *i; } return s; } template void hash_combine(size_t &seed, T const &key) { hash hasher; seed ^= hasher(key) + 0x9e3779b9 + (seed << 6) + (seed >> 2); } namespace std { template struct hash> { size_t operator()(pair const &p) const { size_t seed(0); hash_combine(seed,p.first); hash_combine(seed,p.second); return seed; } }; template struct hash> { size_t operator()(tuple const &t) const { size_t seed(0); hash_combine(seed,get<0>(t)); hash_combine(seed,get<1>(t)); hash_combine(seed,get<2>(t)); return seed; } }; } const auto add = [](auto &x, auto y) { x += y; }; const auto mul = [](auto &x, auto y) { x *= y; }; const auto lam_min = [](auto x, auto y) { return min(x,y); }; const auto lam_max = [](auto x, auto y) { return max(x,y); }; bool odd(i64 x) { return x & 1; } bool even(i64 x) { return !odd(x); } bool parity(i64 x, i64 y) { return odd(x) ^ even(y); } bool bit(i64 n, uint8_t e) { return n >> e & 1; } i64 mask(i64 n, uint8_t e) { return n & (1 << e) - 1; }; int ilog(i64 x, uint64_t b) { if(x) return ilog(x / b,b) + 1; return -1; } i64 qceil(i64 x, i64 y) { return x > 0 ? (x - 1) / y + 1 : x / y; } i64 gcd(i64 a, i64 b) { if(!b) return abs(a); return gcd(b, a % b); } i64 lcm(i64 a, i64 b) { if(a | b) return abs(a / gcd(a, b) * b); return 0; } i64 extgcd(i64 a, i64 b, i64 &x, i64 &y) { i64 d = a; if(b) { d = extgcd(b,a % b,y,x); y -= (a / b) * x; } else { x = 1,y = 0; } return d; } i64 bins(i64 ok, i64 ng, auto judge) { while(abs(ok - ng) > 1) { i64 mid = ok + ng >> 1; (judge(mid) ? ok : ng) = mid; } return ok; } template bool chmax(T& m, U x) { if(m < x) { m = x; return 1; } return 0; } template bool chmin(T& m, U x) { if(m > x) { m = x; return 1; } return 0; } template T cmprs(T& v) { T tmp = v,ret = v; sort(all(tmp)); tmp.erase(unique(all(tmp)),end(tmp)); each(i,ret) *i = l_bnd(all(tmp),*i) - begin(tmp) + 1; return ret; } const int dx[9] = {1,0,-1,0,1,-1,-1,1,0},dy[9] = {0,1,0,-1,1,1,-1,-1,0}; const i64 mod = 1e9 + 7; const db gold = (sqrt(5.0) + 1.0) * 0.5; const db eps = 1e-15; template struct LazySegtree { typedef function opr_t; typedef function lazy_opr_t; typedef function update_opr_t; const opr_t opr; const lazy_opr_t lazy_opr; const update_opr_t update_opr; const Monoid idel,lazy_idel; vector data,lazy; vector lazyflag; int range = 1; LazySegtree(int n, Monoid idel_ = 0, const opr_t &opr_ = plus(), const lazy_opr_t &lazy_opr_ = [](Monoid &x, Monoid y){x += y;}, const update_opr_t &update_opr_ = [](Monoid &x, Monoid y, unsigned int w){x += y * w;}, Monoid lazy_idel_ = 0) : opr(opr_),lazy_opr(lazy_opr_),update_opr(update_opr_),idel(idel_),lazy_idel(lazy_idel_) { while(n >= range) range <<= 1; data.resize(range << 1,idel); lazy.assign(range << 1,lazy_idel); lazyflag.assign(range << 1,false); } void copy(const vector &v) { for(int i = 0; i < v.size(); ++i) data[i + range] = v[i]; for(int i = range - 1; i; --i) data[i] = opr(data[i * 2],data[i * 2 + 1]); } void eval(int k, int l, int r) { if(!lazyflag[k]) return; update_opr(data[k],lazy[k],r - l); if(r - l > 1) { lazy_opr(lazy[k * 2],lazy[k]); lazy_opr(lazy[k * 2 + 1],lazy[k]); lazyflag[k * 2] = lazyflag[k * 2 + 1] = true; } lazy[k] = lazy_idel; lazyflag[k] = false; } void update(int a, int b, Monoid val, int k = 1, int l = 0, int r = -1) { if(r < 0) r = range; eval(k,l,r); if(b <= l || r <= a) return; if(a <= l && r <= b) { lazy_opr(lazy[k],val); lazyflag[k] = true; eval(k,l,r); } else { update(a,b,val,k * 2,l,l + r >> 1); update(a,b,val,k * 2 + 1,l + r >> 1,r); data[k] = opr(data[k * 2],data[k * 2 + 1]); } } Monoid query(int a, int b, int k = 1, int l = 0, int r = -1) { if(r < 0) r = range; eval(k,l,r); if(b <= l || r <= a) return idel; if(a <= l && r <= b) return data[k]; return opr(query(a,b,k * 2,l,l + r >> 1),query(a,b,k * 2 + 1,l + r >> 1,r)); } }; int n; i64 a[1<<17],b[1<<17],ans; int main() { cin>>n; rep(i,1+n) cin>>a[i]; rep(i,1+n) cin>>b[i]; rep(i,n) (b[i+1]+=b[i])%=mod; rep(i,n+1) (ans+=a[i]*b[n-i])%=mod; esc(ans); }