Submission #793572

#	Time	Username	Problem	Language	Result	Execution time	Memory
793572		Jarif_Rahman	Horses (IOI15_horses)	C++17	54 / 100	1580 ms	29876 KiB

horses

#include <bits/stdc++.h>
#define pb push_back
#define f first
#define sc second
using namespace std;
typedef long long int ll;
typedef string str;

const ll md = 1e9+7;
const ll L = 1e9+5;

struct segtree{
    int k = 1;
    vector<ll> P;
    segtree(int n){
        while(k < n) k<<=1;
        P.assign(2*k, 1);
    }
    void update(int i, ll x){
        i+=k;
        P[i] = x%md;
        i>>=1;
        while(i){
            P[i] = (P[i<<1]*P[(i<<1)+1])%md;
            i>>=1;
        }
    }
    ll product(int l, int r, int nd, int a, int b){
        if(a > r || b < l) return 1;
        if(a >= l && b <= r) return P[nd];
        int mid = (a+b)>>1;
        return (product(l, r, nd<<1, a, mid)*product(l, r, (nd<<1)+1, mid+1, b))%md;
    }
    ll product(int l, int r){
        return product(l, r, 1, 0, k-1);
    }
};

int n;
vector<int> X, Y;
segtree seg(0);

int query(){
    int fi = 0;
    for(ll i = n-1, p = 1; i >= 0; i--){
        p*=X[i];
        if(i == 0 || p > L){
            fi = i;
            break;
        }
    }

    ll ans = 0;
    for(ll i = fi, p = 1; i < n; i++, p*=X[i]) ans = max(ans, p*Y[i]);
    ans%=md;
    ans*=seg.product(0, fi), ans%=md;
    return ans;
}

int init(int _n, int _X[], int _Y[]){
    swap(n, _n);
    X.resize(n), Y.resize(n);
    seg = segtree(n);
    for(int i = 0; i < n; i++) X[i] = _X[i], Y[i] = _Y[i], seg.update(i, X[i]);
    return query();
}

int updateX(int i, int x){
    X[i] = x;
    seg.update(i, x);
    return query();
}

int updateY(int i, int y){
    Y[i] = y;
    return query();
}

Compilation message (stderr)

horses.cpp: In function 'int query()':
horses.cpp:48:18: warning: conversion from 'll' {aka 'long long int'} to 'int' may change value [-Wconversion]
   48 |             fi = i;
      |                  ^
horses.cpp:57:12: warning: conversion from 'll' {aka 'long long int'} to 'int' may change value [-Wconversion]
   57 |     return ans;
      |            ^~~

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