#include using namespace std; #define ALL(x) begin(x),end(x) #define rep(i,n) for(int i=0;i<(n);i++) #define debug(v) cout<<#v<<":";for(auto x:v){cout<bool chmax(T &a,const T &b){if(abool chmin(T &a,const T &b){if(b ostream &operator<<(ostream &os,const vector&v){ for(int i=0;i<(int)v.size();i++) os< istream &operator>>(istream &is,vector&v){ for(T &x:v)is>>x; return is; } signed main(){ ll n,k;cin>>n>>k; auto solve=[&](ll l,ll r){ ll ret=1; // a+c=l, 1<=a<=N, 1<=c<=N rep(_,2){ if(l-1<=n) ret*=(l-1); else{ ll sub=l-1-n; ret*=max(0ll,l-1-2*sub); } swap(l,r); } // cout<