Submission #482724

#	Time	Username	Problem	Language	Result	Execution time	Memory
482724		Fysty	A Difficult(y) Choice (BOI21_books)	C++17	100 / 100	4 ms	328 KiB

books

#include <bits/stdc++.h>
//#include "books.h"
#include <random>
#include <chrono>
using namespace std;
//#pragma GCC optimize("Ofast")
//#pragma GCC optimize ("unroll-loops")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
typedef pair<double,double> pdd;
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());

template<typename T> void _do(T x){cerr<<x<<"\n";}
template<typename T,typename ...U> void _do(T x,U ...y){cerr<<x<<", ";_do(y...);}
#define dbg(...) cerr<<#__VA_ARGS__<<" = ";_do(__VA_ARGS__);

const int MOD1=1e9+7;
const int MOD2=998244353;
const ll INF=3e18;
const ld PI=3.14159265358979323846;
ll gcd(ll a,ll b){if(b==0) return a; return gcd(b,a%b);}
ll fpow(ll a,ll b,ll m)
{
    if(!b) return 1;
    ll ans=fpow(a*a%m,b/2,m);
    return (b%2?ans*a%m:ans);
}
ll inv(ll a,ll m) {return fpow(a,m-2,m);}

#define MottoHayaku ios::sync_with_stdio(false);cin.tie(0);
//#define int ll
#define rep(i,n) for(ll i=0;i<n;i++)
#define rep1(i,n) for(ll i=1;i<=n;i++)
#define repk(i,m,n) for(int i=m;i<n;i++)
#define F first
#define S second
#define pb push_back
#define lb lower_bound
#define ub upper_bound
#define uni(c) c.resize(distance(c.begin(),unique(c.begin(),c.end())))
#define unisort(c) sort(c.begin(),c.end()),uni(c)
ll a[100005];
ll skim(int n);
void answer(vector<int> v);
void impossible();
void solve(int n,int k,ll A,int S)
{
    if(n==k)
    {
        ll tot=0;
        vector<int> ans;
        rep1(i,n)
        {
            a[i]=skim(i);
            ans.pb(i);
            tot+=a[i];
        }
        if(tot>=A&&tot<=2*A) answer(ans);
        else impossible();
        return;
    }
    ll tot=0;
    rep1(i,k)
    {
        a[i]=skim(i);
        tot+=a[i];
    }
    if(a[k]>=A)
    {
        if(tot>=A&&tot<=2*A)
        {
            vector<int> ans;
            rep1(i,k) ans.pb(i);
            answer(ans);
        }
        else impossible();
        return;
    }
    ll l=k+1,r=n+1;
    while(l<r)
    {
        ll mid=l+r>>1;
        a[mid]=skim(mid);
        if(a[mid]<A) l=mid+1;
        else r=mid;
    }
    if(l!=n+1)
    {
        if(a[l]==0) a[l]=skim(l);
        vector<int> ans={l};
        tot=a[l];
        rep1(i,k-1)
        {
            tot+=a[i];
            ans.pb(i);
        }
        if(tot>=A&&tot<=2*A)
        {
            answer(ans);
            return;
        }
    }
    l--;
    ll cnt=0;
    for(int i=l;i>=1;i--)
    {
        if(cnt==k) break;
        if(a[i]==0)
        {
            cnt++;
            a[i]=skim(i);
        }
    }
    if(l==k)
    {
        ll tot=0;
        vector<int> ans;
        rep1(i,k)
        {
            ans.pb(i);
            tot+=a[i];
        }
        if(tot>=A&&tot<=2*A) answer(ans);
        else impossible();
        return;
    }
    rep(i,k+1)
    {
        vector<int> ans;
        ll tot=0;
        rep1(j,k-i)
        {
            tot+=a[j];
            ans.pb(j);
        }
        rep(j,i)
        {
            tot+=a[l-j];
            ans.pb(l-j);
        }
        if(tot>=A&&tot<=2*A)
        {
            answer(ans);
            return;
        }
    }
    impossible();
}

Compilation message (stderr)

books.cpp: In function 'void solve(int, int, ll, int)':
books.cpp:86:17: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   86 |         ll mid=l+r>>1;
      |                ~^~
books.cpp:94:26: warning: narrowing conversion of 'l' from 'll' {aka 'long long int'} to 'int' [-Wnarrowing]
   94 |         vector<int> ans={l};
      |                          ^
books.cpp:94:26: warning: narrowing conversion of 'l' from 'll' {aka 'long long int'} to 'int' [-Wnarrowing]

• Subtask 1: 5 / 5
• Subtask 2: 15 / 15
• Subtask 3: 10 / 10
• Subtask 4: 15 / 15
• Subtask 5: 15 / 15
• Subtask 6: 20 / 20
• Subtask 7: 20 / 20