#include <stdio.h>
#define N 100000
#define N2 (N * 2 + 1)
#define N4 (N2 * 2)
#define INF 0x3f3f3f3f
long long min(long long a, long long b) { return a < b ? a : b; }
int solve(int *xx, int n, int s, int x) {
static long long aa[N2], bb[N2], aa_[N4], bb_[N4];
int na, nb, na_, nb_, r, i, ia, ib, j;
long long a, b, tmp;
na = 0;
aa[na++] = x;
for (i = s; i > 0; i--)
aa[na++] = -(xx[i] - xx[i - 1]), aa[na++] = x;
for (i = 1; i < na; i++)
aa[i] += aa[i - 1];
nb = 0;
bb[nb++] = 0;
for (i = s; i + 1 < n; i++)
bb[nb++] = -(xx[i + 1] - xx[i]), bb[nb++] = x;
for (i = 1; i < nb; i++)
bb[i] += bb[i - 1];
for (r = 0; r < 2; r++) {
i = 0, na_ = 0;
while (1) {
aa_[na_++] = aa[i];
j = i + 1, a = aa[i];
while (j < na && (r == 0 ? aa[j] <= aa[i] : aa[j] < aa[i]))
a = min(a, aa[j++]);
if (j == na)
break;
aa_[na_++] = a;
i = j;
}
i = 0, nb_ = 0;
while (1) {
bb_[nb_++] = bb[i];
j = i + 1, b = bb[i];
while (j < nb && (r == 0 ? bb[j] <= bb[i] : bb[j] < bb[i]))
b = min(b, bb[j++]);
if (j == nb)
break;
bb_[nb_++] = b;
i = j;
}
if (aa_[0] + bb_[0] < 0)
return 0;
ia = ib = 0;
while (ia + 2 < na_ || ib + 2 < nb_)
if (ia + 2 < na_ && aa_[ia + 1] + bb_[ib] >= 0)
ia += 2;
else if (ib + 2 < nb_ && aa_[ia] + bb_[ib + 1] >= 0)
ib += 2;
else
return 0;
for (i = 0, j = na - 1; i < j; i++, j--)
tmp = aa[i], aa[i] = aa[j], aa[j] = tmp;
for (i = 0, j = nb - 1; i < j; i++, j--)
tmp = bb[i], bb[i] = bb[j], bb[j] = tmp;
}
return 1;
}
int main() {
static int xx[N];
int n, s, t, i, lower, upper;
scanf("%d%d%d", &n, &s, &t), s--;
for (i = 0; i < n; i++)
scanf("%d", &xx[i]);
lower = -1, upper = INF;
while (upper - lower > 1) {
int v = (lower + upper) / 2;
if (solve(xx, n, s, min((long long) t * v * 2, INF)))
upper = v;
else
lower = v;
}
printf("%d\n", upper);
return 0;
}
Compilation message
sparklers.c: In function 'main':
sparklers.c:72:2: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
72 | scanf("%d%d%d", &n, &s, &t), s--;
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~
sparklers.c:74:3: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
74 | scanf("%d", &xx[i]);
| ^~~~~~~~~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
212 KB |
Output is correct |
| 2 |
Correct |
0 ms |
212 KB |
Output is correct |
| 3 |
Correct |
0 ms |
212 KB |
Output is correct |
| 4 |
Correct |
0 ms |
212 KB |
Output is correct |
| 5 |
Correct |
1 ms |
296 KB |
Output is correct |
| 6 |
Correct |
0 ms |
212 KB |
Output is correct |
| 7 |
Correct |
1 ms |
212 KB |
Output is correct |
| 8 |
Correct |
1 ms |
288 KB |
Output is correct |
| 9 |
Correct |
0 ms |
212 KB |
Output is correct |
| 10 |
Correct |
0 ms |
212 KB |
Output is correct |
| 11 |
Correct |
1 ms |
212 KB |
Output is correct |
| 12 |
Correct |
1 ms |
212 KB |
Output is correct |
| 13 |
Correct |
0 ms |
292 KB |
Output is correct |
| 14 |
Correct |
1 ms |
212 KB |
Output is correct |
| 15 |
Correct |
0 ms |
212 KB |
Output is correct |
| 16 |
Correct |
0 ms |
292 KB |
Output is correct |
| 17 |
Correct |
0 ms |
212 KB |
Output is correct |
| 18 |
Correct |
1 ms |
292 KB |
Output is correct |
| 19 |
Correct |
0 ms |
288 KB |
Output is correct |
| 20 |
Correct |
0 ms |
212 KB |
Output is correct |
| 21 |
Correct |
0 ms |
292 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
212 KB |
Output is correct |
| 2 |
Correct |
0 ms |
212 KB |
Output is correct |
| 3 |
Correct |
0 ms |
212 KB |
Output is correct |
| 4 |
Correct |
0 ms |
212 KB |
Output is correct |
| 5 |
Correct |
1 ms |
296 KB |
Output is correct |
| 6 |
Correct |
0 ms |
212 KB |
Output is correct |
| 7 |
Correct |
1 ms |
212 KB |
Output is correct |
| 8 |
Correct |
1 ms |
288 KB |
Output is correct |
| 9 |
Correct |
0 ms |
212 KB |
Output is correct |
| 10 |
Correct |
0 ms |
212 KB |
Output is correct |
| 11 |
Correct |
1 ms |
212 KB |
Output is correct |
| 12 |
Correct |
1 ms |
212 KB |
Output is correct |
| 13 |
Correct |
0 ms |
292 KB |
Output is correct |
| 14 |
Correct |
1 ms |
212 KB |
Output is correct |
| 15 |
Correct |
0 ms |
212 KB |
Output is correct |
| 16 |
Correct |
0 ms |
292 KB |
Output is correct |
| 17 |
Correct |
0 ms |
212 KB |
Output is correct |
| 18 |
Correct |
1 ms |
292 KB |
Output is correct |
| 19 |
Correct |
0 ms |
288 KB |
Output is correct |
| 20 |
Correct |
0 ms |
212 KB |
Output is correct |
| 21 |
Correct |
0 ms |
292 KB |
Output is correct |
| 22 |
Correct |
1 ms |
340 KB |
Output is correct |
| 23 |
Correct |
1 ms |
296 KB |
Output is correct |
| 24 |
Correct |
1 ms |
340 KB |
Output is correct |
| 25 |
Correct |
1 ms |
340 KB |
Output is correct |
| 26 |
Correct |
1 ms |
340 KB |
Output is correct |
| 27 |
Correct |
1 ms |
296 KB |
Output is correct |
| 28 |
Correct |
1 ms |
300 KB |
Output is correct |
| 29 |
Correct |
1 ms |
340 KB |
Output is correct |
| 30 |
Correct |
1 ms |
300 KB |
Output is correct |
| 31 |
Correct |
1 ms |
340 KB |
Output is correct |
| 32 |
Correct |
1 ms |
340 KB |
Output is correct |
| 33 |
Correct |
1 ms |
296 KB |
Output is correct |
| 34 |
Correct |
1 ms |
340 KB |
Output is correct |
| 35 |
Correct |
1 ms |
340 KB |
Output is correct |
| 36 |
Correct |
1 ms |
300 KB |
Output is correct |
| 37 |
Correct |
1 ms |
300 KB |
Output is correct |
| 38 |
Correct |
1 ms |
340 KB |
Output is correct |
| 39 |
Correct |
1 ms |
340 KB |
Output is correct |
| 40 |
Correct |
1 ms |
340 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
212 KB |
Output is correct |
| 2 |
Correct |
0 ms |
212 KB |
Output is correct |
| 3 |
Correct |
0 ms |
212 KB |
Output is correct |
| 4 |
Correct |
0 ms |
212 KB |
Output is correct |
| 5 |
Correct |
1 ms |
296 KB |
Output is correct |
| 6 |
Correct |
0 ms |
212 KB |
Output is correct |
| 7 |
Correct |
1 ms |
212 KB |
Output is correct |
| 8 |
Correct |
1 ms |
288 KB |
Output is correct |
| 9 |
Correct |
0 ms |
212 KB |
Output is correct |
| 10 |
Correct |
0 ms |
212 KB |
Output is correct |
| 11 |
Correct |
1 ms |
212 KB |
Output is correct |
| 12 |
Correct |
1 ms |
212 KB |
Output is correct |
| 13 |
Correct |
0 ms |
292 KB |
Output is correct |
| 14 |
Correct |
1 ms |
212 KB |
Output is correct |
| 15 |
Correct |
0 ms |
212 KB |
Output is correct |
| 16 |
Correct |
0 ms |
292 KB |
Output is correct |
| 17 |
Correct |
0 ms |
212 KB |
Output is correct |
| 18 |
Correct |
1 ms |
292 KB |
Output is correct |
| 19 |
Correct |
0 ms |
288 KB |
Output is correct |
| 20 |
Correct |
0 ms |
212 KB |
Output is correct |
| 21 |
Correct |
0 ms |
292 KB |
Output is correct |
| 22 |
Correct |
1 ms |
340 KB |
Output is correct |
| 23 |
Correct |
1 ms |
296 KB |
Output is correct |
| 24 |
Correct |
1 ms |
340 KB |
Output is correct |
| 25 |
Correct |
1 ms |
340 KB |
Output is correct |
| 26 |
Correct |
1 ms |
340 KB |
Output is correct |
| 27 |
Correct |
1 ms |
296 KB |
Output is correct |
| 28 |
Correct |
1 ms |
300 KB |
Output is correct |
| 29 |
Correct |
1 ms |
340 KB |
Output is correct |
| 30 |
Correct |
1 ms |
300 KB |
Output is correct |
| 31 |
Correct |
1 ms |
340 KB |
Output is correct |
| 32 |
Correct |
1 ms |
340 KB |
Output is correct |
| 33 |
Correct |
1 ms |
296 KB |
Output is correct |
| 34 |
Correct |
1 ms |
340 KB |
Output is correct |
| 35 |
Correct |
1 ms |
340 KB |
Output is correct |
| 36 |
Correct |
1 ms |
300 KB |
Output is correct |
| 37 |
Correct |
1 ms |
300 KB |
Output is correct |
| 38 |
Correct |
1 ms |
340 KB |
Output is correct |
| 39 |
Correct |
1 ms |
340 KB |
Output is correct |
| 40 |
Correct |
1 ms |
340 KB |
Output is correct |
| 41 |
Correct |
26 ms |
3268 KB |
Output is correct |
| 42 |
Correct |
2 ms |
432 KB |
Output is correct |
| 43 |
Correct |
19 ms |
1044 KB |
Output is correct |
| 44 |
Correct |
39 ms |
4772 KB |
Output is correct |
| 45 |
Correct |
38 ms |
4768 KB |
Output is correct |
| 46 |
Correct |
39 ms |
4820 KB |
Output is correct |
| 47 |
Correct |
51 ms |
4684 KB |
Output is correct |
| 48 |
Correct |
39 ms |
4784 KB |
Output is correct |
| 49 |
Correct |
37 ms |
4772 KB |
Output is correct |
| 50 |
Correct |
38 ms |
4676 KB |
Output is correct |
| 51 |
Correct |
50 ms |
4788 KB |
Output is correct |
| 52 |
Correct |
43 ms |
4772 KB |
Output is correct |
| 53 |
Correct |
40 ms |
4776 KB |
Output is correct |
| 54 |
Correct |
50 ms |
4784 KB |
Output is correct |
| 55 |
Correct |
39 ms |
4692 KB |
Output is correct |
| 56 |
Correct |
37 ms |
4692 KB |
Output is correct |
| 57 |
Correct |
37 ms |
4748 KB |
Output is correct |
| 58 |
Correct |
40 ms |
4748 KB |
Output is correct |
| 59 |
Correct |
43 ms |
5528 KB |
Output is correct |
| 60 |
Correct |
41 ms |
4768 KB |
Output is correct |
| 61 |
Correct |
37 ms |
4684 KB |
Output is correct |
| 62 |
Correct |
37 ms |
4692 KB |
Output is correct |
| 63 |
Correct |
37 ms |
4692 KB |
Output is correct |
| 64 |
Correct |
37 ms |
4740 KB |
Output is correct |
| 65 |
Correct |
41 ms |
4784 KB |
Output is correct |
| 66 |
Correct |
38 ms |
4756 KB |
Output is correct |
| 67 |
Correct |
40 ms |
4692 KB |
Output is correct |
| 68 |
Correct |
38 ms |
4692 KB |
Output is correct |
| 69 |
Correct |
38 ms |
4656 KB |
Output is correct |
