| # | Time | Username | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 1286707 | user736482 | A Difficult(y) Choice (BOI21_books) | C++20 | 0 ms | 0 KiB |
void solve(int a,int b,long long c,int d);
/*
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.
*/
#include<vector>
#include<cstdio>
#include<set>
#include<cstdlib>
#include<cstdarg>
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);
}
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");
}
#pragma GCC optimize("O3")
#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define ld long double
#define pb push_back
#define ff first
#define ss second
#define MOD 998244353LL
#define INF 1000000001LL
#define POT (1LL<<20)
#define INFL 1000000000000000099LL
#define pii pair<ll,ll>
#define ppi pair<pii,ll>
#define pip pair<ll,pii>
#define ppp pair<pii,pii>
#define vi vector<ll>
#define vii vector<pii>
#define al(x) x.begin(),x.end()
#define rev(x) reverse(al(x))
#define X 18
template<typename T, typename U>
pair<T, U> operator+(const pair<T, U>& a, const pair<T, U>& b) {
return {a.first + b.first, a.second + b.second};
}
template<typename T, typename U>
pair<T, U> operator-(const pair<T, U>& a, const pair<T, U>& b) {
return {a.first - b.first, a.second - b.second};
}
template<typename T, typename U>
ostream& operator<<(ostream& os, const pair<T, U>& p) {
os<<"{"<<p.ff<<", "<<p.ss<<"}";
return os;
}
template<typename T>
ostream& operator<<(ostream& os, const vector<T>& v) {
os << "{";
for (size_t i = 0; i < v.size(); ++i) {
if (i) os << ", ";
os << v[i];
}
os << "}";
return os;
}
void solve(int N,int K,ll a,int S){
ll n=N;
ll k=K;
ll s=S;
vi v;
ll b=0;
for(ll i=1;i<k;i++){
v.pb(skim(i));
b+=v.back();
}
ll pocz=k;
ll kon=n+1;
ll x,y=INFL;
while(pocz!=kon){
ll md=(pocz+kon)/2;
x=skim(md);
if(b+x<a)pocz=md+1;
else {kon=md;y=x;}
}
if(b+y<=2*a){
vector<int>ans;
for(ll i=1;i<k;i++)ans.pb(i);
ans.pb(pocz);
answer(ans);return;
}
x=pocz-1;
if(x<k){
impossible();return;
}
vector<int>ans;
v.pb(0);
for(ll i=1;i<=k;i++){
ans.pb(x);
b+=skim(x);
b-=v[v.size()-i];
x--;
if(b>=a){
for(ll j=1;j<=k-i;j++)ans.pb(j);
answer(ans);
}
}
impossible();
}