oj.uz

Submission #425428

# Submission time Handle Problem Language Result Execution time Memory
425428 2021-06-13T03:22:42 Z Kevin_Zhang_TW Sparklers (JOI17_sparklers) C++17
50 / 100
 30 ms 1356 KB 
#include<bits/stdc++.h>
#define pb emplace_back
#define AI(i) begin(i), end(i)
using namespace std;
using ll = long long;
template<class T> bool chmin(T &a, T b) { return b < a && (a = b, true); }
template<class T> bool chmax(T &a, T b) { return a < b && (a = b, true); }
#ifdef KEV
#define DE(args...) kout("[ " + string(#args) + " ] = ", args)
void kout() {cerr << endl;}
template<class T, class ...U> void kout (T v, U ...e) { cerr << v << ' ', kout(e...); }
template<class T> void debug(T L, T R) { while (L != R) cerr << *L << " \n"[next(L)==R], ++L; }
#else
#define DE(...) 0
#define debug(...) 0
#endif
// What I should check
// 1. overflow
// 2. corner cases
// Enjoy the problem instead of hurrying to AC
// Good luck !
const int MAX_N = 1010;
 
const ll inf = 1ll << 55;
 
int n, k, T;
int pos[MAX_N];
 
bool dp[MAX_N][MAX_N];
ll a[MAX_N];

bool valid(ll S) {
	memset(dp, 0, sizeof(dp));

	dp[k][k] = true;
	for (int l = k;l >= 1;--l)
		for (int r = k;r <= n;++r) {

			auto valid = [&](ll d) {
				return 2 * S * (r-l+1) * T - (pos[r] - pos[l]) >= d;
			};
			
			if (dp[l][r]) {
				if (r < n) {
					ll d = pos[r+1] - pos[r];
					if (valid(d))
						dp[l][r+1] = true;
				}
				if (l > 1) {
					ll d = pos[l] - pos[l-1];
					if (valid(d))
						dp[l-1][r] = true;
				}
			}
		}

	return dp[1][n];
}
 
int32_t main() {
	ios_base::sync_with_stdio(0), cin.tie(0);
	cin >> n >> k >> T;
	for (int i = 1;i <= n;++i)
		cin >> pos[i];
 
	//if (n <= 1) return puts("0"), 0;

	assert(n < MAX_N);
 
	ll L = 0, R = 2 * pos[n], M;
 
	while (L < R) {
		M = L + R >> 1;
		if (valid(M))
			R = M;
		else L = M + 1;
	}
 
	cout << L << '\n';
	
}

Compilation message

sparklers.cpp: In function 'int32_t main()':
sparklers.cpp:73:9: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   73 |   M = L + R >> 1;
      |       ~~^~~

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 1228 KB Output is correct
2 Correct 2 ms 1228 KB Output is correct
3 Correct 2 ms 1228 KB Output is correct
4 Correct 2 ms 1228 KB Output is correct
5 Correct 2 ms 1228 KB Output is correct
6 Correct 2 ms 1228 KB Output is correct
7 Correct 2 ms 1228 KB Output is correct
8 Correct 2 ms 1228 KB Output is correct
9 Correct 2 ms 1228 KB Output is correct
10 Correct 2 ms 1228 KB Output is correct
11 Correct 2 ms 1228 KB Output is correct
12 Correct 2 ms 1228 KB Output is correct
13 Correct 3 ms 1228 KB Output is correct
14 Correct 2 ms 1228 KB Output is correct
15 Correct 2 ms 1228 KB Output is correct
16 Correct 2 ms 1228 KB Output is correct
17 Correct 2 ms 1228 KB Output is correct
18 Correct 2 ms 1228 KB Output is correct
19 Correct 1 ms 204 KB Output is correct
20 Correct 2 ms 1228 KB Output is correct
21 Correct 1 ms 204 KB Output is correct

Subtask #2
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 1228 KB Output is correct
2 Correct 2 ms 1228 KB Output is correct
3 Correct 2 ms 1228 KB Output is correct
4 Correct 2 ms 1228 KB Output is correct
5 Correct 2 ms 1228 KB Output is correct
6 Correct 2 ms 1228 KB Output is correct
7 Correct 2 ms 1228 KB Output is correct
8 Correct 2 ms 1228 KB Output is correct
9 Correct 2 ms 1228 KB Output is correct
10 Correct 2 ms 1228 KB Output is correct
11 Correct 2 ms 1228 KB Output is correct
12 Correct 2 ms 1228 KB Output is correct
13 Correct 3 ms 1228 KB Output is correct
14 Correct 2 ms 1228 KB Output is correct
15 Correct 2 ms 1228 KB Output is correct
16 Correct 2 ms 1228 KB Output is correct
17 Correct 2 ms 1228 KB Output is correct
18 Correct 2 ms 1228 KB Output is correct
19 Correct 1 ms 204 KB Output is correct
20 Correct 2 ms 1228 KB Output is correct
21 Correct 1 ms 204 KB Output is correct
22 Correct 16 ms 1328 KB Output is correct
23 Correct 12 ms 1228 KB Output is correct
24 Correct 6 ms 1228 KB Output is correct
25 Correct 3 ms 1228 KB Output is correct
26 Correct 16 ms 1332 KB Output is correct
27 Correct 18 ms 1228 KB Output is correct
28 Correct 29 ms 1228 KB Output is correct
29 Correct 23 ms 1328 KB Output is correct
30 Correct 21 ms 1332 KB Output is correct
31 Correct 25 ms 1332 KB Output is correct
32 Correct 27 ms 1228 KB Output is correct
33 Correct 28 ms 1228 KB Output is correct
34 Correct 16 ms 1356 KB Output is correct
35 Correct 30 ms 1320 KB Output is correct
36 Correct 10 ms 1328 KB Output is correct
37 Correct 9 ms 1228 KB Output is correct
38 Correct 25 ms 1228 KB Output is correct
39 Correct 11 ms 1328 KB Output is correct
40 Correct 1 ms 204 KB Output is correct

Subtask #3
0 / 50.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 1228 KB Output is correct
2 Correct 2 ms 1228 KB Output is correct
3 Correct 2 ms 1228 KB Output is correct
4 Correct 2 ms 1228 KB Output is correct
5 Correct 2 ms 1228 KB Output is correct
6 Correct 2 ms 1228 KB Output is correct
7 Correct 2 ms 1228 KB Output is correct
8 Correct 2 ms 1228 KB Output is correct
9 Correct 2 ms 1228 KB Output is correct
10 Correct 2 ms 1228 KB Output is correct
11 Correct 2 ms 1228 KB Output is correct
12 Correct 2 ms 1228 KB Output is correct
13 Correct 3 ms 1228 KB Output is correct
14 Correct 2 ms 1228 KB Output is correct
15 Correct 2 ms 1228 KB Output is correct
16 Correct 2 ms 1228 KB Output is correct
17 Correct 2 ms 1228 KB Output is correct
18 Correct 2 ms 1228 KB Output is correct
19 Correct 1 ms 204 KB Output is correct
20 Correct 2 ms 1228 KB Output is correct
21 Correct 1 ms 204 KB Output is correct
22 Correct 16 ms 1328 KB Output is correct
23 Correct 12 ms 1228 KB Output is correct
24 Correct 6 ms 1228 KB Output is correct
25 Correct 3 ms 1228 KB Output is correct
26 Correct 16 ms 1332 KB Output is correct
27 Correct 18 ms 1228 KB Output is correct
28 Correct 29 ms 1228 KB Output is correct
29 Correct 23 ms 1328 KB Output is correct
30 Correct 21 ms 1332 KB Output is correct
31 Correct 25 ms 1332 KB Output is correct
32 Correct 27 ms 1228 KB Output is correct
33 Correct 28 ms 1228 KB Output is correct
34 Correct 16 ms 1356 KB Output is correct
35 Correct 30 ms 1320 KB Output is correct
36 Correct 10 ms 1328 KB Output is correct
37 Correct 9 ms 1228 KB Output is correct
38 Correct 25 ms 1228 KB Output is correct
39 Correct 11 ms 1328 KB Output is correct
40 Correct 1 ms 204 KB Output is correct
41 Runtime error 2 ms 460 KB Execution killed with signal 11
42 Halted 0 ms 0 KB -