#include // cout, endl, cin #include // string, to_string, stoi #include // vector #include // min, max, swap, sort, reverse, lower_bound, upper_bound #include // pair, make_pair #include // tuple, make_tuple #include // int64_t, int*_t #include // printf #include // map #include // queue, priority_queue #include // set #include // stack #include // deque #include // unordered_map #include // unordered_set #include // bitset #include // isupper, islower, isdigit, toupper, tolower #include //fixed,setprecision //#include //INT_MAX //#include //M_PI #include #include // 正規表現 #include //#include using namespace std; #include using namespace atcoder; using mint = modint1000000007; //using mint = modint998244353; //using mint=modint; template bool chmax(T &u, const T z) { if (u < z) {u = z; return true;} else return false; } template bool chmin(T &u, const T z) { if (u > z) {u = z; return true;} else return false; } #define ll long long #define rep(i, n) for (ll i = 0; i < (ll)(n); i++) //typedef pair P; //typedef pairP; //typedef pair q; ll gcd(ll x, ll y) { return y ? gcd(y, x % y) : x; } ll lcm(ll a, ll b){return a * b / gcd(a, b);} //contain(string s,string v) sにvが含まれるかを判定 template bool contain(const std::basic_string& s, const U& v) { return s.find(v) != std::basic_string::npos; } //回転 void rot(vector& a){ int h=a.size(),w=a[0].size(); vector p(w,string(h,'?')); swap(a,p); rep(i,h)rep(j,w)a[j][h-1-i]=p[i][j];} //二分探索 #define bis(_ac,_wa,_f) [&]{ll ac=_ac,wa=_wa;while(abs(ac-wa)>1){ll wj=(ac+wa)/2;(_f(wj)?ac:wa)=wj;}return ac;}() int main(){ ll a,b; cin>>a>>b; if(a>0&&a