| # | Time | Username | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 556940 | kym | A Difficult(y) Choice (BOI21_books) | C++14 | 0 ms | 0 KiB |
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <bits/stdc++.h>
using namespace std;
#include "books.h"
#define s second
#define f first
#define pb push_back
#define FOR(i,s,e) for(ll i = s; i <= (ll)e; ++i)
typedef pair <long long ,int> pi;
using namespace std;
#ifdef LOCAL
#define db(x) cerr << #x << "=" << x << "\n"
#define db2(x, y) cerr << #x << "=" << x << " , " << #y << "=" << y << "\n"
#define db3(a,b,c) cerr<<#a<<"="<<a<<","<<#b<<"="<<b<<","<<#c<<"="<<c<<"\n"
#define dbv(v) cerr << #v << ":"; for (auto ite : v) cerr << ite << ' '; cerr <<"\n"
#define dbvp(v) cerr << #v << ":"; for (auto ite : v) cerr << "{" << ite.f << ',' << ite.s << "} "; cerr << "\n"
#define dba(a,ss,ee) cerr << #a << ":"; FOR(ite,ss,ee) cerr << a[ite] << ' '; cerr << "\n"
#define reach cerr << "LINE: " << __LINE__ << "\n";
#else
#define db(x)
#define db2(x,y)
#define db3(a,b,c)
#define dbv(v)
#define dbvp(v)
#define dba(a,ss,ee)
#define reach
#endif
//
// --- Sample implementation for the task books ---
//
// To compile this program with the sample grader, place:
// books.h books_sample.cpp sample_grader.cpp
// in a single folder and run:
// g++ books_sample.cpp sample_grader.cpp
// in this folder.
//
/*
SAMPLE GRADER for task BOOKS
USAGE:
place together with your solution and books.h in the same directory, then:
g++ <flags> sample_grader.cpp <solution_file>
e.g.:
g++ -std=c++17 sample_grader.cpp books.cpp
INPUT/OUTPUT:
The sample grader expects on standard input two lines. The first line should
contain the four integers N, K, A and S. The second line should contain a list
of N integers, the sequence of difficulties x_1 x_2 ... x_N which has to be
strictly increasing. Then, the grader writes to standard output a protocol of
all grader functions called by your program.
At the end, the grader prints your verdict.
*/
#ifndef LOCAL
#include<vector>
#include<cstdio>
#include<set>
#include<cstdlib>
#include<cstdarg>
#include<cassert>
#include"books.h"
using namespace std;
typedef long long ll;
void __attribute__((noreturn)) __attribute__((format(printf, 1, 2))) result(const char *msg, ...)
{
va_list args;
va_start(args, msg);
vfprintf(stderr, msg, args);
fprintf(stderr, "\n");
va_end(args);
exit(0);
}
namespace
{
int N, K, S, sUsed;
long long A;
vector<long long> seq;
}
void impossible()
{
result("Impossible (not checked): %d book(s) skimmed", sUsed);
exit(0);
}
long long skim(int pos)
{
printf("skim(%d): ", pos);
if (pos<1 || pos>N) result("Invalid skim");
printf("%lld\n", seq[pos]);
sUsed++;
if (sUsed>S) result("Out of books to skim");
return seq[pos];
}
void answer(vector<int> v)
{
printf("answer({");
for(int i = 0; i < (int) v.size(); ++i)
{
printf("%d", v[i]);
if(i + 1 != (int) v.size()) printf(", ");
}
printf("})\n");
if ((int) v.size() != K) result("Invalid answer");
ll sum = 0;
for(auto x: v) {
if (x<1 || x>N) result("Invalid answer");
sum += seq[x];
}
if (sum < A || 2*A<sum) result("Wrong answer");
result("Correct: %d book(s) skimmed", sUsed);
exit(0);
}
#endif
void solve(int n, int k, long long a, int s) {
ll lo = 0, hi = n+1;
while(lo<hi-1) {
ll mid = (lo+hi)/2;
ll x = skim(mid);
if(x*k >= a)hi=mid;
else lo=mid;
}
cerr << hi << '\n';
vector<pi> v;
FOR(i,hi-k,hi+k) {
if(i<=0||i>n)continue;
v.pb(pi(skim(i),i));
}
FOR(i,0,(1<<(v.size()))-1) {
if(__builtin_popcount(i) != k)continue;
int tot = 0;
vector<int> res;
FOR(j,0,v.size()-1) {
if(i&(1<<j)) {
tot += v[j].f;
res.pb(v[j].s);
}
}
dbv(res);
db(tot);
if(tot >= a && tot <= 2*a){
answer(res);
//exit(0);
}
}
impossible();
}
#ifndef LOCAL
int main()
{
if(scanf("%d %d %lld %d", &N, &K, &A, &S) != 4)
result("Invalid input");
seq.resize(N + 1);
for(int i = 1; i <= N; ++i) {
if(scanf("%lld", &(seq[i])) != 1) result("Invalid input");
if(i>1 && seq[i]<=seq[i-1]) result("Invalid input");
}
solve(N, K, A, S);
result("No answer");
}
#endif