Submission #1098683

#	Time	Username	Problem	Language	Result	Execution time	Memory
1098683		Tymond	Horses (IOI15_horses)	C++17	17 / 100	63 ms	29268 KiB

horses

#include <bits/stdc++.h>
#include "horses.h"
using namespace std;
using ll = long long;
using ld = long double;
#define fi first
#define se second
#define vi vector<int>
#define vll vector<long long>
#define pii pair<int, int>
#define pll pair<long long, long long>
#define pb push_back
#define mp make_pair
#define eb emplace_back
#define all(x) (x).begin(), (x).end()
#define sz(x) (int)(x).size()
mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
mt19937_64 rng64(chrono::high_resolution_clock::now().time_since_epoch().count());
inline int rand(int l,int r){return uniform_int_distribution<int>(l, r)(rng);}
inline ll rand(ll l,ll r){return uniform_int_distribution<ll>(l, r)(rng64);}
#ifdef DEBUG
auto&operator<<(auto&o,pair<auto,auto>p){return o<<"("<<p.first<<", "<<p.second<<")";}
auto operator<<(auto&o,auto x)->decltype(x.end(),o){o<<"{";int i=0;for(auto e:x)o<<","+!i++<<e;return o<<"}";}
#define debug(X...)cerr<<"["#X"]: ",[](auto...$){((cerr<<$<<"; "),...)<<endl;}(X)
#else
#define debug(...){}
#endif
 
struct custom_hash {
    static uint64_t splitmix64(uint64_t x) {
        x += 0x9e3779b97f4a7c15;
        x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9;
        x = (x ^ (x >> 27)) * 0x94d049bb133111eb;
        return x ^ (x >> 31);
    }
 
    size_t operator()(uint64_t x) const {
        static const uint64_t FIXED_RANDOM = chrono::steady_clock::now().time_since_epoch().count();
        return splitmix64(x + FIXED_RANDOM);
    }
};

const int MOD = 1e9 + 7;
const int MAXN = 5e5 + 7;
const int BASE = (1 << 19);
ll tree[2 * BASE + 7];
ll lazy[2 * BASE + 7];
int Y[MAXN];
int X[MAXN];
int n;

ll inv(ll a){
    if(a <= 1){
        return a;
    }
    return MOD - (ll)(MOD / a) * inv(MOD % a) % MOD;
}

void Push(int v){
    tree[2 * v] = (ll)tree[2 * v] * lazy[v];
    tree[2 * v] %= MOD;
    tree[2 * v + 1] = (ll)tree[2 * v + 1] * lazy[v];
    tree[2 * v + 1] %= MOD;
    lazy[v] = 1LL;
}

int init(int N, int Xn[], int Yn[]){
    n = N;
    for(int i = 0; i < n; i++){
        X[i] = Xn[i];
        Y[i] = Yn[i];
    }

    for(int i = 1; i < 2 * BASE + 7; i++){
        lazy[i] = 1LL;
    }

    ll mul = 1LL;
    for(int i = 0; i < n; i++){
        mul = (ll)mul * X[i];
        mul %= MOD;
        tree[i + BASE] = (ll)mul * Y[i];
        tree[i + BASE] %= MOD;
    }

    for(int i = BASE - 1; i >= 1; i--){
        tree[i] = max(tree[2 * i], tree[2 * i + 1]);
    }

    return (int)tree[1];
}

void change(int v, int l, int p, int a, int b, ll val){
    if(p < a || b < l){
        return;
    }

    if(a <= l && p <= b){
        tree[v] = (ll)tree[v] * val;
        tree[v] %= MOD;
        lazy[v] = (ll)lazy[v] * val;
        lazy[v] %= MOD;
        return;
    }
    Push(v);

    int mid = (l + p) / 2;
    change(2 * v, l, mid ,a ,b ,val);
    change(2 * v + 1, mid + 1, p, a, b, val);
    tree[v] = max(tree[2 * v], tree[2 * v + 1]);
}

int updateX(int pos, int val){
    change(1, 0, BASE - 1, pos, n - 1, ((ll)val * inv(X[pos])) % MOD);
    X[pos] = val;

    return (int)tree[1];
}

int updateY(int pos, int val){
    int v = 1;
    pii range = mp(0, BASE - 1);
    for(int i = 18; i >= 0; i--){
        Push(v);
        if(pos <= range.fi + (1 << i) - 1){
            v *= 2;
            range.se = range.fi + (1 << i) - 1;
        }else{
            v = 2 * v + 1;
            range.fi = range.se - (1 << i) + 1;
        }
    }

    pos += BASE;
    tree[pos] = (ll)((ll)tree[pos] * inv(Y[pos - BASE]) % MOD) * val % MOD;
    tree[pos] %= MOD;
    Y[pos - BASE] = val;
    pos /= 2;
    while(pos > 0){
        tree[pos] = max(tree[2 * pos], tree[2 * pos + 1]);
        pos /= 2;
    }

    return (int)tree[1];
}

/*int main(){
    int p[3] = {2, 1, 3};
    int d[3] = {3, 4, 1};
    cout << init(3, p, d) << '\n';
    cout << updateY(1, 2) << '\n';

    return 0;
}*/

• Subtask 1: 17 / 17
• Subtask 2: 0 / 17
• Subtask 3: 0 / 20
• Subtask 4: 0 / 23
• Subtask 5: 0 / 23