oj.uz

Submission #187536

# Submission time Handle Problem Language Result Execution time Memory
187536 2020-01-13T02:50:09 Z dndhk Watching (JOI13_watching) C++14
50 / 100
 1000 ms 808 KB 
#include <bits/stdc++.h>

#define pb push_back

using namespace std;

typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

const int MAX_N = 2002;
const ll INFLL = 10000;
int N, P, Q;
vector<ll> v;

list<pii> dq[2][MAX_N+1];

void add(int idx, int x, int y, int z){
	while(!dq[idx][x].empty() && dq[idx][x].back().first>=z){
		dq[idx][x].pop_back();
	}
	dq[idx][x].push_back({z, y});
}

bool chk(ll x){
	for(int i=0; i<=N; i++){
		while(!dq[0][i].empty())	dq[0][i].pop_back();
		while(!dq[1][i].empty())	dq[1][i].pop_back();
	}
	dq[0][0].pb({0, 0});
	//cout<<x<<endl;
	int r1=0, r2=0, k;
	for(int i=0; i<=N; i++){
		while(r1<v.size()-1 && v[r1+1]<=v[i+1]+x-1LL){
			r1++;
		}
		while(r2<v.size()-1 && v[r2+1]<=v[i+1]+2LL*x-1LL){
			r2++;
		}
		for(int j=N; j>=0; j--){
			while(!dq[0][j].empty() && dq[0][j].front().second<i)	dq[0][j].pop_front();
			while(!dq[1][j].empty() && dq[1][j].front().second<i)	dq[1][j].pop_front();
			if(dq[0][j].empty()){
				if(!dq[1][j].empty())	k = dq[1][j].front().first;
				else continue;
			}else{
				if(dq[1][j].empty())	k = dq[0][j].front().first;
				else{
					k = min(dq[0][j].front().first, dq[1][j].front().first);
				}
			}
			if(i==N){
				if(j<=P && k<=Q)	return true;
			}else{
				add(0, j+1, r1, k);
				add(1, j, r2, k+1);
			}
		}
	}
	return false;
}

int main(){
	scanf("%d%d%d", &N, &P, &Q);	
	v.pb(0);
	for(int i=1; i<=N; i++){
		ll x; scanf("%lld", &x);
		v.pb(x);
	}
	sort(v.begin(), v.end());
	v.erase(unique(v.begin(), v.end()), v.end());
	sort(v.begin(), v.end());
	N = v.size()-1;
	ll s = 1LL, e = 1000000000LL, m;
	while(s<e){
		m = (s+e)/2LL;
		if(chk(m)){
			e = m;
		}else{
			s = m+1;
		}
	}
	printf("%lld", s);
}

Compilation message

watching.cpp: In function 'bool chk(ll)':
watching.cpp:34:11: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   while(r1<v.size()-1 && v[r1+1]<=v[i+1]+x-1LL){
         ~~^~~~~~~~~~~
watching.cpp:37:11: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   while(r2<v.size()-1 && v[r2+1]<=v[i+1]+2LL*x-1LL){
         ~~^~~~~~~~~~~
watching.cpp: In function 'int main()':
watching.cpp:64:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d%d", &N, &P, &Q); 
  ~~~~~^~~~~~~~~~~~~~~~~~~~~~
watching.cpp:67:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   ll x; scanf("%lld", &x);
         ~~~~~^~~~~~~~~~~~

Subtask #1
50.0 / 50.0

# Verdict Execution time Memory Grader output
1 Correct 16 ms 376 KB Output is correct
2 Correct 2 ms 376 KB Output is correct
3 Correct 1 ms 376 KB Output is correct
4 Correct 16 ms 504 KB Output is correct
5 Correct 20 ms 376 KB Output is correct
6 Correct 16 ms 504 KB Output is correct
7 Correct 15 ms 376 KB Output is correct
8 Correct 17 ms 376 KB Output is correct
9 Correct 17 ms 376 KB Output is correct
10 Correct 17 ms 376 KB Output is correct
11 Correct 16 ms 376 KB Output is correct
12 Correct 17 ms 504 KB Output is correct
13 Correct 13 ms 376 KB Output is correct
14 Correct 16 ms 376 KB Output is correct
15 Correct 16 ms 504 KB Output is correct

Subtask #2
0 / 50.0

# Verdict Execution time Memory Grader output
1 Execution timed out 1016 ms 808 KB Time limit exceeded
2 Halted 0 ms 0 KB -