#include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include using namespace std; //#define int long long typedef long long ll; typedef unsigned long long ul; typedef unsigned int ui; const ll mod = 998244353; const ll INF = mod * mod; typedef pair P; #define stop char nyaa;cin>>nyaa; #define rep(i,n) for(int i=0;i=0;i--) #define Rep(i,sta,n) for(int i=sta;i=1;i--) #define Rep1(i,sta,n) for(int i=sta;i<=n;i++) typedef pair LP; typedef vector vec; typedef vector svec; typedef long double ld; typedef pair LDP; const ld eps = 1e-8; void solve() { ll h, w; cin >> h >> w; w = abs(w); ll ad = h - (w-1); ad = max((ll)ad, (ll)0); h -= ad; ll ans = ad; if (h == 0) { cout << ans << endl; return; } /*else if (h == 1) { cout << ans + w << endl; return; }*/ ll tmp = 2; ll cur = 1; while (cur <= h) { cur += tmp; tmp++; } tmp--; cur -= tmp; ll loc = 0; ll sum = 0; vector v; rep1(i, tmp - 1) { ll len = i; if (loc + len > w) { v.push_back({ loc,w - loc }); sum += (w - loc)*i; loc = w; break; } v.push_back({ loc,len }); sum += len * i; loc += len; } if (loc < w)sum += (w - loc)*(tmp - 1); //cout << sum << endl; ll lenq = w - h+1; ll dif = h - cur; ll d = lenq / tmp; sum += d * dif; sum += min(dif, lenq%tmp); ll locc = w - 1; ll id = (int)v.size() - 1; rep(i, tmp) { if (loc <= 0)break; if (locc < v[id].first) { id--; } ll val = id + 1; if (locc >= h && ((locc - h) % tmp) < dif)val++; if (locc + val > w)sum++; locc--; } cout << ans + sum << endl; } signed main() { ios::sync_with_stdio(false); cin.tie(0); cout << fixed << setprecision(10); //init(); solve(); //cout << "finish" << endl; //stop return 0; }