oj.uz

Submission #802562

# Submission time Handle Problem Language Result Execution time Memory
802562 2023-08-02T12:46:06 Z KN200711 Watching (JOI13_watching) C++14
50 / 100
 1000 ms 31188 KB 
# include <bits/stdc++.h>
# define ll long long
using namespace std;

int N, P, Q;
vector<int> arr;

int mn[2001][2001];
int edge[2][2001];

bool cek(int a) {
	// set edge nya dulu
	for(int i=0;i<N;i++) {
		int T = arr[i] + a - 1;
		edge[0][i] = upper_bound(arr.begin(), arr.end(), T) - arr.begin();
		T += a;
		edge[1][i] = upper_bound(arr.begin(), arr.end(), T) - arr.begin();
		
	//	if(a == 4) cout<<i<<" "<<edge[0][i]<<" "<<edge[1][i]<<endl;
	}
	
	priority_queue< pair<int, pair<int, int> > > PQ;
	PQ.push(make_pair(0, make_pair(0, 0)));
	
	vector< pair<int, int> > ST;
	ST.clear();
	
	while(!PQ.empty()) {
		int x, y, z;
		x = PQ.top().second.first;
		y = PQ.top().second.second;
		z = PQ.top().first;
		PQ.pop();
		if(-z > Q) continue;
		if(mn[x][-y] != 1e9) continue;
	//	if(a == 1) cout<<x<<" "<<y<<" "<<z<<endl;
		ST.push_back(make_pair(x, -y));
		mn[x][-y] = z;
		if(x == N) {
			for(auto p : ST) mn[p.first][p.second] = 1e9;
			return 1;
		}
		
		PQ.push(make_pair(z, make_pair(edge[0][x], y-1)));
		PQ.push(make_pair(z-1, make_pair(edge[1][x], y)));
	}
	for(auto p : ST) mn[p.first][p.second] = 1e9;
	return 0;
}

int main() {
	scanf("%d %d %d", &N, &P, &Q);
	arr.resize(N);
	for(int i=0;i<N;i++) scanf("%d", &arr[i]);
	sort(arr.begin(), arr.end());
	
	if(P + Q >= N) {
		printf("1\n");
		return 0;
	}
	
	for(int i=0;i<=N;i++) {
		for(int k=0;k<=P;k++) mn[i][k] = 1e9;
	}
//	cout<<cek(4)<<endl;
	int l = 1, r = 1e9, ans = -1;
	while(l <= r) {
		int mid = (l + r) / 2;
		if(cek(mid)) {
			ans = mid;
			r = mid - 1;
		} else l = mid + 1;
	}
	printf("%d\n", ans);
}

Compilation message

watching.cpp: In function 'int main()':
watching.cpp:52:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   52 |  scanf("%d %d %d", &N, &P, &Q);
      |  ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
watching.cpp:54:28: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   54 |  for(int i=0;i<N;i++) scanf("%d", &arr[i]);
      |                       ~~~~~^~~~~~~~~~~~~~~

Subtask #1
50.0 / 50.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 724 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 1 ms 340 KB Output is correct
4 Correct 1 ms 212 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 0 ms 212 KB Output is correct
7 Correct 1 ms 596 KB Output is correct
8 Correct 1 ms 724 KB Output is correct
9 Correct 1 ms 724 KB Output is correct
10 Correct 3 ms 724 KB Output is correct
11 Correct 5 ms 688 KB Output is correct
12 Correct 6 ms 724 KB Output is correct
13 Correct 1 ms 724 KB Output is correct
14 Correct 1 ms 724 KB Output is correct
15 Correct 1 ms 724 KB Output is correct

Subtask #2
0 / 50.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 8276 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 1 ms 320 KB Output is correct
4 Correct 1 ms 316 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 1 ms 212 KB Output is correct
7 Correct 9 ms 8404 KB Output is correct
8 Correct 366 ms 11364 KB Output is correct
9 Correct 624 ms 17644 KB Output is correct
10 Correct 197 ms 19472 KB Output is correct
11 Correct 441 ms 12420 KB Output is correct
12 Execution timed out 1084 ms 31188 KB Time limit exceeded
13 Halted 0 ms 0 KB -