Submission #1175110

#	Time	Username	Problem	Language	Result	Execution time	Memory
1175110		Zero_OP	Arboras (RMI20_arboras)	C++20	11 / 100	5092 ms	3348 KiB

arboras

#include <bits/stdc++.h>

using namespace std;

#define FOR(i, l, r) for(int i = (l); i < (r); ++i)
#define ROF(i, r, l) for(int i = (r)-1; i >= (l); --i)

#define mp make_pair
#define mt make_tuple
#define ff first
#define ss second

#define all(v) begin(v), end(v)
#define rall(v) rbegin(v), rend(v)
#define pb push_back
#define eb emplace_back
#define sz(v) (int)v.size()
#define compact(v) v.erase(unique(all(v)), end(v))

#define dbg(x) "[" #x " = " << (x) << "]"

template<typename T>
      bool minimize(T& a, const T& b){
            if(a > b) return a = b, true;
            return false;
      }

template<typename T>
      bool maximize(T& a, const T& b){
            if(a < b) return a = b, true;
            return false;
      }

using ll = long long;
using db = double;
using ld = long double;
using ull = unsigned long long;

using pi = pair<int, int>;
using pl = pair<ll, ll>;

using vi = vector<int>;
using vl = vector<ll>;
using vd = vector<db>;
using vc = vector<char>;
using vb = vector<bool>;

using vpi = vector<pi>;
using vpl = vector<pl>;

using vvi = vector<vi>;
using vvl = vector<vl>;
using vvc = vector<vc>;

void setIO(){
      ios_base::sync_with_stdio(0); cin.tie(0);
#ifdef LOCAL
      freopen("task.inp", "r", stdin);
      freopen("task.out", "w", stdout);
#endif // LOCAL
}

const int MAX = 1e5 + 5;
const int mod = 1e9 + 7;

struct mint{
      int v;
      mint(int v = 0) : v(v) {}

      mint& operator += (const mint& o){ v += o.v; if(v >= mod) v -= mod; return *this; }
      mint& operator -= (const mint& o){ v -= o.v; if(v < 0) v += mod; return *this; }
      mint& operator *= (const mint& o){ v -= o.v; if(v < 0) v += mod; return *this; }

      mint power(ll n) const {
            mint res(1), base = *this;
            for(; n > 0; n >>= 1, base *= base){
                  if(n & 1) res *= base;
            }
            return res;
      }

      mint inv() const {
            return power(mod-2);
      }

      mint& operator /= (const mint& o){ return *this *= o.inv(); }

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

      friend ostream& operator << (ostream& out, const mint& o){ return out << o.v; }

      friend bool operator == (const mint& a, const mint& b){ return a.v == b.v; }
      friend bool operator != (const mint& a, const mint& b){ return a.v != b.v; }
};

int N, p[MAX];
ll d[MAX];
ll f1[MAX], f2[MAX];

mint calc(){
      mint ans = 0;
      FOR(i, 0, N) f1[i] = 0, f2[i] = 0;
      ROF(i, N, 1){
            ans += mint((f1[i] + f2[i]) % mod);
            if(f1[p[i]] < f1[i] + d[i]){
                  f2[p[i]] = f1[p[i]];
                  f1[p[i]] = f1[i] + d[i];
            } else maximize(f2[p[i]], f1[i] + d[i]);
      }
      ans += mint((f1[0] + f2[0]) % mod);
      return ans;
}

int main(){
      setIO();

      cin >> N;
      FOR(i, 1, N) cin >> p[i];
      FOR(i, 1, N) cin >> d[i];

      cout << calc() << '\n';
      int Q; cin >> Q;
      while(Q--){
            int v, add;
            cin >> v >> add;
            d[v] += add;
            cout << calc() << '\n';
      }

      return 0;
}

• Subtask 1: 11 / 11
• Subtask 2: 0 / 13
• Subtask 3: 0 / 31
• Subtask 4: 0 / 45