Submission #206930

#	Time	Username	Problem	Language	Result	Execution time	Memory
206930		oscarsierra12	Horses (IOI15_horses)	C++14	17 / 100	1502 ms	38520 KiB

horses

#include "horses.h"
#include <bits/stdc++.h>

#define ff       first
#define ss       second
#define pb       push_back

using namespace std ;

typedef long long     ll ;
typedef pair<ll, pair<ll,int>> iii ;

const int N = 1e7 ;
const int o = 5e5+2 ;
const int mod = 1e9+7 ;

int lft[N], rg[N];
ll mx[N], mult[N] ;
int supMod[N] ;
int cntNode = 0 ;
int x[o], y[o] ;
int n ;

void build ( int nod, int l, int r ) {
    int mid = (l+r)/2 ;
    if ( l == r ) {
        mx [nod] = y[l] ;
        mult [nod] = x[l] ;
        return ;
    }
    build ( lft[nod] = ++cntNode , l, mid ) ;
    build ( rg[nod] = ++cntNode , mid+1, r ) ;
    mx[nod] = max ( mx[lft[nod]], mx[rg[nod]] ) ;
    mult[nod] = mult[lft[nod]] * mult[rg[nod]] ;
    if ( mult[nod] > mod ) supMod[nod] = 1 ;
    else supMod[nod] = (supMod[lft[nod]] | supMod[rg[nod]]) ;
    mult[nod] %= mod ;
}

void update ( int nod, int l, int r, int a, int x, int y ) {
    int mid = (l+r)/2 ;
    if ( l == a && r == a ) {
        mx[nod] = y ;
        mult[nod] = x ;
        return ;
    }
    if ( a <= mid ) update ( lft[nod], l, mid, a, x, y ) ;
    else update ( rg[nod], mid+1, r, a, x, y ) ;
    mx[nod] = max ( mx[lft[nod]], mx[rg[nod]] ) ;
    mult[nod] = mult[lft[nod]] * mult[rg[nod]] ;
    if ( mult[nod] > mod ) supMod[nod] = 1 ;
    else supMod[nod] = (supMod[lft[nod]] | supMod[rg[nod]]) ;
    mult[nod] %= mod ;
}

iii query ( int nod, int l, int r, int a, int b ) {
    int mid = (l+r)/2 ;
    if ( a > b ) return {1,{1,1}};
    if ( l == a && r == b ) return {mx[nod], {mult[nod], supMod[nod]}} ;
    if ( b <= mid ) return query ( lft[nod], l, mid, a, b ) ;
    if ( a > mid ) return query ( rg[nod], mid+1, r, a, b ) ;
    iii L = query ( lft[nod], l, mid, a, mid ) ;
    iii R = query ( rg[nod], mid+1, r, mid+1, b ) ;
    return {max (L.ff, R.ff), {1ll*(L.ss.ff * R.ss.ff)%mod, (L.ss.ff * R.ss.ff > mod || L.ss.ss || R.ss.ss )}};
}

int solve () {
    int l = 0, r = n-1 ;
    while ( l < r ) {
        int mid = (l+r) / 2 ;
        if ( query(0,0,n-1,mid,n-1).ss.ss ) l = mid+1 ;
        else r = mid ;
    }
    ll ans = query(0,0,n-1,0,l-1).ss.ff ;
    int lst = l-1 ;
    ll psb = (l?x[l-1] * y[l-1]:0) ;
    ll best = 0, cur = 1 ;
    int bg = l ;
    while ( bg < n ) {
        l = bg, r = n ;
        while ( l < r ) {
            int mid = (l+r)/2 ;
            if ( query(0,0,n-1,bg,mid).ss.ff == x[bg] ) l = mid+1 ;
            else r = mid ;
        }
        best = max ( best, cur * query(0,0,n-1,bg,l-1).ff * x[bg] ) ;
        cur *= x[bg] ;
        bg = l ;
    }
    if ( psb > best ) return (ans*y[lst])%mod ;
    best %= mod ;
    return (ans*best)%mod ;
}

int init(int Ne, int X[], int Y[]) {
    for ( int i = 0 ; i < Ne; ++i )
        x[i] = X[i], y[i] = Y[i] ;
    n = Ne ;
    build ( 0,0,n-1 ) ;
    return solve();
}

int updateX(int pos, int val) {
    update ( 0,0,n-1,pos,val,y[pos]) ;
    x[pos] = val ;
	return solve();
}

int updateY(int pos, int val) {
    update ( 0,0,n-1,pos,x[pos],val) ;
    y[pos] = val ;
	return solve();
}

Compilation message (stderr)

horses.cpp: In function 'void update(int, int, int, int, int, int)':
horses.cpp:40:58: warning: declaration of 'y' shadows a global declaration [-Wshadow]
 void update ( int nod, int l, int r, int a, int x, int y ) {
                                                          ^
horses.cpp:21:11: note: shadowed declaration is here
 int x[o], y[o] ;
           ^
horses.cpp:40:58: warning: declaration of 'x' shadows a global declaration [-Wshadow]
 void update ( int nod, int l, int r, int a, int x, int y ) {
                                                          ^
horses.cpp:21:5: note: shadowed declaration is here
 int x[o], y[o] ;
     ^
horses.cpp: In function 'int solve()':
horses.cpp:90:42: warning: conversion to 'int' from 'll {aka long long int}' may alter its value [-Wconversion]
     if ( psb > best ) return (ans*y[lst])%mod ;
                              ~~~~~~~~~~~~^~~~
horses.cpp:92:22: warning: conversion to 'int' from 'll {aka long long int}' may alter its value [-Wconversion]
     return (ans*best)%mod ;
            ~~~~~~~~~~^~~~

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