Submission #1266857

#	Time	Username	Problem	Language	Result	Execution time	Memory
1266857		farica	Harbingers (CEOI09_harbingers)	C++20	100 / 100	133 ms	20644 KiB

harbingers

#include<bits/stdc++.h>
using namespace std;
using vi = vector<int>;
using pi = pair<int,int>;
typedef long long ll;
#define debug(x) cout << #x << " = " << x << "\n";
#define vdebug(a) cout << #a << " = "; for(auto x: a) cout << x << " "; cout << "\n";

const int MOD = 1e9 + 7;
const int INF = 1e9;

template<ll mod>
struct modnum {
	static constexpr bool is_big_mod = mod > numeric_limits<int>::max();

	using S = conditional_t<is_big_mod, ll, int>;
	using L = conditional_t<is_big_mod, __int128, ll>;

	S x;

	modnum() : x(0) {}
	modnum(ll _x) {
		_x %= static_cast<ll>(mod);
		if (_x < 0) { _x += mod; }
		x = _x;
	}

	modnum pow(ll n) const {
		modnum res = 1;
		modnum cur = *this;
		while (n > 0) {
			if (n & 1) res *= cur;
			cur *= cur;
						n /= 2;
		}
		return res;
	}
	modnum inv() const { return (*this).pow(mod-2); }

	modnum& operator+=(const modnum& a){
		x += a.x;
		if (x >= mod) x -= mod;
		return *this;
	}
	modnum& operator-=(const modnum& a){
		if (x < a.x) x += mod;
		x -= a.x;
		return *this;
	}
	modnum& operator*=(const modnum& a){
		x = static_cast<L>(x) * a.x % mod;
		return *this;
	}
	modnum& operator/=(const modnum& a){ return *this *= a.inv(); }

	friend modnum operator+(const modnum& a, const modnum& b){ return modnum(a) += b; }
	friend modnum operator-(const modnum& a, const modnum& b){ return modnum(a) -= b; }
	friend modnum operator*(const modnum& a, const modnum& b){ return modnum(a) *= b; }
	friend modnum operator/(const modnum& a, const modnum& b){ return modnum(a) /= b; }

	friend bool operator==(const modnum& a, const modnum& b){ return a.x == b.x; }
	friend bool operator!=(const modnum& a, const modnum& b){ return a.x != b.x; }
	friend bool operator<(const modnum& a, const modnum& b){ return a.x < b.x; }

	friend ostream& operator<<(ostream& os, const modnum& a){ os << a.x; return os; }
	friend istream& operator>>(istream& is, modnum& a) { ll x; is >> x; a = modnum(x); return is; }
};

using mint = modnum<MOD>;

template <class T> class SumSegmentTree {
  private:
	const T DEFAULT = 0;

	vector<T> segtree;
	int len;

  public:
	SumSegmentTree(int len) : len(len), segtree(len * 2, DEFAULT) {}

	void set(int ind, T val) {
		ind += len;
		segtree[ind] = val;
		for (; ind > 1; ind /= 2) {
			segtree[ind / 2] = segtree[ind] + segtree[ind ^ 1];
		}
	}

	T range_sum(int start, int end) {
		T sum = DEFAULT;
		for (start += len, end += len; start < end; start /= 2, end /= 2) {
			if (start % 2 == 1) { sum += segtree[start++]; }
			if (end % 2 == 1) { sum += segtree[--end]; }
		}
		return sum;
	}
};

/*
const int N = 250005;

struct BIT {
  ll b[N], n;

  void init(int _n) {
	n = _n ;
	for(int i = 0 ; i <= n ; ++i) b[i] = 0;
  }
  inline int lowbit(int x) { return x & (-x); }
  void update(int x, ll v) {
	for(int i = x ; i <= n ; i += lowbit(i)) b[i] += v;
  }
  ll query(int x) {
	ll ans = 0;
	for(int i = x ; i > 0 ; i -= lowbit(i)) ans += b[i];
	return ans;
  }
} bit[2]; */

int gcd(int a, int b, int& x, int& y) { // x*a + y*b = a1
    x = 1, y = 0;
    int x1 = 0, y1 = 1, a1 = a, b1 = b;
    while (b1) {
        int q = a1 / b1;
        tie(x, x1) = make_tuple(x1, x - q * x1);
        tie(y, y1) = make_tuple(y1, y - q * y1);
        tie(a1, b1) = make_tuple(b1, a1 - q * b1);
    }
    return a1;
}

int inv_ecd(int a, int m) {
	int x, y;
	int g = gcd(a, m, x, y);
	if(g != 1) return -1;
	x = (x + m) % m;
	return x;
}

const int maxn = 1e5 + 1;
using ld = long double;

struct Line {
	ll m, b;

	Line(ll m = 0, ll b = 0) : m(m), b(b) {}

	ll operator()(ll x) { return m * x + b; }

	friend ld intersect(Line l1, Line l2) {
		return (ld)(l2.b - l1.b) / (ld)(l1.m - l2.m);
	}
};

int n, siz;
Line stk[maxn];
vector<pi>adjL[maxn];
vi v, s;
vector<ll>ans;

int remove_pos(Line line) {
    if(siz < 2 or intersect(line, stk[siz-1]) >= intersect(stk[siz-1], stk[siz-2])) return siz;
    int l=1, r=siz-1;
    while(l<r) {
        int m = (l+r)/2;
        if(intersect(line, stk[m]) < intersect(stk[m], stk[m-1])) r=m;
        else l=m+1;
    }
    return l;
}

ll get_min(ll x) {
    int l=0, r=siz-1;
    while(l<r) {
        int m = (l+r)/2;
        if(intersect(stk[m], stk[m+1]) < x) l = m+1;
        else r = m;
    }
    return stk[l](x);
}

void dfs(int pos, ll d, int prev=0) {
    int prev_siz, prev_pos;
    Line prev_line;
    if(!pos) {
        ans[pos] = 0;
        stk[siz++] = {0,0};
    } else {
        ans[pos] = get_min(v[pos]) + 1LL * d * v[pos] + s[pos];
        Line tmp(-d, ans[pos]);
        prev_siz = siz;
        prev_pos = siz = remove_pos(tmp);
        prev_line = stk[siz];
        stk[siz++] = tmp;
    }
    for(auto [V,W]: adjL[pos]) {
        if(V == prev) continue;
        dfs(V, d+W, pos);
    }
    if(pos) {
        siz = prev_siz;
        stk[prev_pos] = prev_line;
    }
}

void solve() {
    cin >> n;
    v.resize(n);
    s.resize(n);
    ans.resize(n);
    for(int i=0; i<n-1; ++i) {
        int u,v,d;
        cin >> u >> v >> d;
        --u, --v;
        adjL[u].push_back({v,d});
        adjL[v].push_back({u,d});
    }
    for(int i=1; i<n; ++i) cin >> s[i] >> v[i];
    dfs(0, 0);
    for(int i=1; i<n; ++i) cout << ans[i] << endl;
}

int main(){
	ios::sync_with_stdio(0);
	cin.tie(0); cout.tie(0);

	//freopen("strange_file.txt", "r", stdin);
	//freopen("strange_file3.txt", "w", stdout);

	int tc = 1;
	while (tc--) solve();
}

• Subtask 1: 100 / 100