Submission #404377

#	Time	Username	Problem	Language	Result	Execution time	Memory
404377		AmineWeslati	A Difficult(y) Choice (BOI21_books)	C++14	25 / 100	4 ms	3520 KiB

books

//Never stop trying
#include "bits/stdc++.h"
#include "books.h"
using namespace std;
#define boost ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0)

typedef long long ll;
typedef string str;
typedef long double ld;
typedef pair<int, int> pi;
#define fi first
#define se second
typedef vector<int> vi;
typedef vector<pi> vpi;
#define pb push_back
#define eb emplace_back
#define sz(x) (int)x.size()
#define all(x) begin(x), end(x)
#define rall(x) rbegin(x), rend(x)
#define endl "\n"
#define FOR(i,a,b) for (int i = (a); i < (b); ++i)
#define ROF(i,a,b) for (int i = (b)-1; i >= (a); --i)

const int MOD = 1e9 + 7; //998244353
const ll INF = 1e18;
const int MX = 2e5 + 10;
const int nx[4] = {0, 0, 1, -1}, ny[4] = {1, -1, 0, 0}; //right left down up

template<class T> using V = vector<T>;
template<class T> bool ckmin(T& a, const T& b) { return a > b ? a = b, 1 : 0; }
template<class T> bool ckmax(T& a, const T& b) { return a < b ? a = b, 1 : 0; }
ll cdiv(ll a, ll b) { return a / b + ((a ^ b) > 0 && a % b); } // divide a by b rounded up
//constexpr int log2(int x) { return 31 - __builtin_clz(x); } // floor(log2(x))

mt19937 rng(chrono::system_clock::now().time_since_epoch().count());
//mt19937_64 rng(chrono::system_clock::now().time_since_epoch().count());
ll random(ll a, ll b){
    return a + rng() % (b - a + 1);
}
#ifndef LOCAL  
#define cerr if(false) cerr
#endif
#define dbg(x) cerr << #x << " : " << x << endl; 
#define dbgs(x,y) cerr << #x << " : " << x << " / " << #y << " : " << y << endl;
#define dbgv(v) cerr << #v << " : " << "[ "; for(auto it : v) cerr << it << ' '; cerr << ']' << endl;
#define here() cerr << "here" << endl;

void IO() {
#ifdef LOCAL
    freopen("input.txt", "r", stdin); 
    freopen("output.txt", "w", stdout);
#endif
}
/////////////////////////ONLY CLEAN CODES ALLOWED/////////////////////////


vector<ll>memo(MX,-1);
ll get(int i){
	if(memo[i]!=-1) return memo[i]; 
	return memo[i]=skim(i);
}

void solve(int N, int K, ll A, int S) {
	ll x=0;
	FOR(i,1,K+1) x+=get(i);
	if(x>2*A) impossible();

	vi ans(K); iota(all(ans),1);

	int idx,l=1,r=N;
	while(l<=r){
		int m=(l+r)/2;
		if(skim(m)<=A){
			idx=m; 
			l=m+1;
		}
		else r=m-1;
	}
	if(idx+1<=N && x-skim(K)+skim(idx+1)<=2*A){
		ans[K-1]=idx+1;
		answer(ans);
	}

	int i=1;
	while(idx && x<A){
		ans[i-1]=idx;
		x-=skim(i); i++;
		x+=skim(idx); idx--;
	}
	if(x>=A && x<=2*A) answer(ans);
	impossible();
}

//Change your approach 

Compilation message (stderr)

books.cpp: In function 'void solve(int, int, ll, int)':
books.cpp:70:6: warning: 'idx' may be used uninitialized in this function [-Wmaybe-uninitialized]
   70 |  int idx,l=1,r=N;
      |      ^~~

• Subtask 1: 0 / 5
• Subtask 2: 0 / 15
• Subtask 3: 10 / 10
• Subtask 4: 15 / 15
• Subtask 5: 0 / 15
• Subtask 6: 0 / 20
• Subtask 7: 0 / 20