제출 #620779

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
620779		A_D	말 (IOI15_horses)	C++14	0 / 100	236 ms	92924 KiB

horses

#include "horses.h"

#include <bits/stdc++.h>

using namespace std;

const int N=1e6+100;
const long long MOD=1e9+7;
long long x[N];
long long y[N];
set<int> st;
long long sum=1;
int n;
vector<int> vec;
long long seg[4*N];

long long po(long long b,long long p)
{
    if(p==0)return 1;
    if(p==1)return b;
    if(p%2){
        return (b*po(b,p-1))%MOD;
    }
    long long r=po(b,p/2);
    return (r*r)%MOD;
}


long long modinv(int v)
{
    return po(v,MOD-2);
}




void build(int p,int s,int e)
{
    if(s==e){
        seg[p]=y[s];
        return;
    }
    int mid=(s+e)/2;
    build(p*2,s,mid);
    build(p*2+1,mid+1,e);
    seg[p]=max(seg[p*2],seg[p*2+1]);
}

void update(int p,int s,int e,int i,int val)
{
    if(s==e){
        seg[p]=val;
        return;
    }
    int mid=(s+e)/2;
    if(i<=mid){
        update(p*2,s,mid,i,val);
    }
    else{
        update(p*2+1,mid+1,e,i,val);
    }
    seg[p]=max(seg[p*2],seg[p*2+1]);
}

long long get(int p,int s,int e,int a,int b)
{
    if(a<=s&&e<=b){
        return seg[p];
    }
    if(s>b||e<a)return 0;
    int mid=(s+e)/2;
    return max(get(p*2,s,mid,a,b),get(p*2+1,mid+1,e,a,b));
}
long long getansst()
{
    long long ret=seg[1];
    long long sum=1;
    for(auto i:vec){
        sum*=x[i];
        long long u=sum*get(1,0,n-1,i,n-1);
        if(u>ret){
            sum%=MOD;
            ret=sum*get(1,0,n-1,i,n-1);
        }
    }
    ret%=MOD;
}
void filvec()
{
    vec.clear();
    int cnt=0;
    for(auto x:st){
        cnt++;
        if(cnt==31)continue;
        vec.push_back(-x);
    }
    reverse(vec.begin(),vec.end());
}

int init(int N, int X[], int Y[]){
    st.clear();
    n=N;
    for(int i=0;i<N;i++){
        x[i]=X[i];
        y[i]=Y[i];
        if(x[i]!=1){
            st.insert(-i);
        }
    }
    build(1,0,n-1);
    filvec();



    if(vec.empty()){
        sum=1;
        return seg[1];
    }
    else{
        int h=vec[0];
        for(int i=0;i<h;i++){
            sum*=x[i];
            sum%=MOD;
        }

        long long u=getansst();
        u*=sum;
        u%=MOD;
        return (int)u;

    }

}

int updateX(int pos, int val) {

    filvec();
    int sz=vec.size();
    if(x[pos]!=1){
        st.erase(-pos);
    }
    if(val!=1){
        st.insert(-pos);
    }
    if(st.size()<=31){
        filvec();
        x[pos]=val;
        sum=1;
        long long u=getansst();
        return (int)u;
    }
    else{
        int h=vec[0];
        if(pos<h){
            sum*=modinv(x[pos]);
            sum%=MOD;
            x[pos]=val;
            sum*=x[pos];
            sum%=MOD;
        }
        else{

            if(val!=1){
                st.erase(-pos);
            }

            if(x[pos]!=1){
                st.insert(-pos);
            }




            if(x[pos]!=1){
                if(val!=1){
                    x[pos]=val;
                }
                else{
                    int cnt=0;
                    int u;
                    for(auto x:st){
                        cnt++;
                        u=x;
                        if(cnt==32)break;
                    }
                    u*=-1;
                    st.erase(pos);
                    sum*=modinv(x[u]);
                    sum%=MOD;
                    x[pos]=val;
                }
            }
            else{
                if(val!=1){
                    x[pos]=val;
                    st.insert(-pos);
                    sum*=vec[h];
                    sum%=MOD;
                }
                else{
                    x[pos]=val;
                }
            }
        }
    }












    long long u=getansst();

    u*=sum;

    u%=MOD;


    return (int)u;
}

int updateY(int pos, int val) {

    update(1,0,n-1,pos,val);

    long long u=getansst();

    u*=sum;

    u%=MOD;


    return (int)u;



}

컴파일 시 표준 에러 (stderr) 메시지

horses.cpp: In function 'long long int getansst()':
horses.cpp:77:15: warning: declaration of 'sum' shadows a global declaration [-Wshadow]
   77 |     long long sum=1;
      |               ^~~
horses.cpp:12:11: note: shadowed declaration is here
   12 | long long sum=1;
      |           ^~~
horses.cpp:87:1: warning: no return statement in function returning non-void [-Wreturn-type]
   87 | }
      | ^
horses.cpp: In function 'void filvec()':
horses.cpp:92:14: warning: declaration of 'x' shadows a global declaration [-Wshadow]
   92 |     for(auto x:st){
      |              ^
horses.cpp:9:11: note: shadowed declaration is here
    9 | long long x[N];
      |           ^
horses.cpp: In function 'int init(int, int*, int*)':
horses.cpp:100:14: warning: declaration of 'N' shadows a global declaration [-Wshadow]
  100 | int init(int N, int X[], int Y[]){
      |          ~~~~^
horses.cpp:7:11: note: shadowed declaration is here
    7 | const int N=1e6+100;
      |           ^
horses.cpp:117:21: warning: conversion from 'long long int' to 'int' may change value [-Wconversion]
  117 |         return seg[1];
      |                ~~~~~^
horses.cpp: In function 'int updateX(int, int)':
horses.cpp:138:20: warning: conversion from 'std::vector<int>::size_type' {aka 'long unsigned int'} to 'int' may change value [-Wconversion]
  138 |     int sz=vec.size();
      |            ~~~~~~~~^~
horses.cpp:155:30: warning: conversion from 'long long int' to 'int' may change value [-Wconversion]
  155 |             sum*=modinv(x[pos]);
      |                         ~~~~~^
horses.cpp:181:30: warning: declaration of 'x' shadows a global declaration [-Wshadow]
  181 |                     for(auto x:st){
      |                              ^
horses.cpp:9:11: note: shadowed declaration is here
    9 | long long x[N];
      |           ^
horses.cpp:188:36: warning: conversion from 'long long int' to 'int' may change value [-Wconversion]
  188 |                     sum*=modinv(x[u]);
      |                                 ~~~^
horses.cpp:138:9: warning: unused variable 'sz' [-Wunused-variable]
  138 |     int sz=vec.size();
      |         ^~
horses.cpp:186:22: warning: 'u' may be used uninitialized in this function [-Wmaybe-uninitialized]
  186 |                     u*=-1;
      |                     ~^~~~

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