#include <bits/stdc++.h>
#define ll long long
#define ull unsigned long long
#define lsb(x) (x & (-x))
using namespace std;
const int MAXN = (int)1e6;
int arr[2 * MAXN + 1];
pair<int, int> dp[2 * MAXN + 1];
int main() {
#ifdef HOME
ifstream cin("C.in");
ofstream cout("C.out");
#endif
int i, j, n;
ios::sync_with_stdio(false);
cin.tie(0), cout.tie(0);
cin >> n;
n *= 2;
for(i = 1; i <= n; i++) {
cin >> arr[2 * i - 1];
}
for(i = 1; i <= n; i++) {
cin >> arr[2 * i];
}
for(i = 1; i <= 2 * n; i++) {
dp[i].first = 2 * n;
dp[i].second = -2 * n;
int cur = 1;
if(i % 2 == 0) {
cur = -1;
}
for(j = i - 1; j >= max(0, i - 3); j--) {
if((i + 1) / 2 - (j + 1) / 2 == 1 && arr[j] <= arr[i]) {
dp[i].first = min(dp[i].first, dp[j].first + cur);
dp[i].second = max(dp[i].second, dp[j].second + cur);
}
}
//cerr << arr[i] << " " << dp[i].first << " " << dp[i].second << "\n";
}
string str;
int pos = 2 * n;
if(dp[2 * n - 1].first <= 0 && dp[2 * n - 1].second >= 0) {
pos = 2 * n - 1;
}
if(dp[pos].first > 0 || dp[pos].second < 0) {
cout << -1;
return 0;
}
int val = 0;
while(pos != 0) {
int cur = 1;
if(pos & 1) {
str += 'A';
}
else {
str += 'B';
cur = -1;
}
//cerr << pos << "\n";
for(j = pos - 1; j >= max(0, pos - 3); j--) {
if(arr[pos] >= arr[j] && (pos + 1) / 2 - (j + 1) / 2 == 1 && dp[j].first + cur <= val && dp[j].second + cur >= val) {
pos = j, val -= cur;
break;
}
}
}
reverse(str.begin(), str.end());
cout << str;
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
4 ms |
384 KB |
Output is correct |
2 |
Correct |
4 ms |
384 KB |
Output is correct |
3 |
Correct |
4 ms |
384 KB |
Output is correct |
4 |
Correct |
5 ms |
384 KB |
Output is correct |
5 |
Correct |
6 ms |
384 KB |
Output is correct |
6 |
Correct |
6 ms |
384 KB |
Output is correct |
7 |
Correct |
6 ms |
512 KB |
Output is correct |
8 |
Correct |
6 ms |
512 KB |
Output is correct |
9 |
Correct |
6 ms |
384 KB |
Output is correct |
10 |
Correct |
8 ms |
384 KB |
Output is correct |
11 |
Correct |
6 ms |
384 KB |
Output is correct |
12 |
Correct |
6 ms |
512 KB |
Output is correct |
13 |
Correct |
6 ms |
512 KB |
Output is correct |
14 |
Correct |
5 ms |
384 KB |
Output is correct |
15 |
Correct |
6 ms |
512 KB |
Output is correct |
16 |
Correct |
6 ms |
384 KB |
Output is correct |
17 |
Correct |
6 ms |
512 KB |
Output is correct |
18 |
Correct |
6 ms |
512 KB |
Output is correct |
19 |
Correct |
6 ms |
512 KB |
Output is correct |
20 |
Correct |
5 ms |
512 KB |
Output is correct |
21 |
Correct |
5 ms |
512 KB |
Output is correct |
22 |
Correct |
5 ms |
384 KB |
Output is correct |
23 |
Correct |
6 ms |
512 KB |
Output is correct |
24 |
Correct |
6 ms |
512 KB |
Output is correct |
25 |
Correct |
5 ms |
512 KB |
Output is correct |
26 |
Correct |
5 ms |
384 KB |
Output is correct |
27 |
Correct |
5 ms |
512 KB |
Output is correct |
28 |
Correct |
5 ms |
384 KB |
Output is correct |
29 |
Correct |
5 ms |
512 KB |
Output is correct |
30 |
Correct |
5 ms |
512 KB |
Output is correct |
31 |
Correct |
6 ms |
512 KB |
Output is correct |
32 |
Correct |
5 ms |
384 KB |
Output is correct |
33 |
Correct |
5 ms |
384 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
4 ms |
384 KB |
Output is correct |
2 |
Correct |
4 ms |
384 KB |
Output is correct |
3 |
Correct |
4 ms |
384 KB |
Output is correct |
4 |
Correct |
5 ms |
384 KB |
Output is correct |
5 |
Correct |
6 ms |
384 KB |
Output is correct |
6 |
Correct |
6 ms |
384 KB |
Output is correct |
7 |
Correct |
6 ms |
512 KB |
Output is correct |
8 |
Correct |
6 ms |
512 KB |
Output is correct |
9 |
Correct |
6 ms |
384 KB |
Output is correct |
10 |
Correct |
8 ms |
384 KB |
Output is correct |
11 |
Correct |
6 ms |
384 KB |
Output is correct |
12 |
Correct |
6 ms |
512 KB |
Output is correct |
13 |
Correct |
6 ms |
512 KB |
Output is correct |
14 |
Correct |
5 ms |
384 KB |
Output is correct |
15 |
Correct |
6 ms |
512 KB |
Output is correct |
16 |
Correct |
6 ms |
384 KB |
Output is correct |
17 |
Correct |
6 ms |
512 KB |
Output is correct |
18 |
Correct |
6 ms |
512 KB |
Output is correct |
19 |
Correct |
6 ms |
512 KB |
Output is correct |
20 |
Correct |
5 ms |
512 KB |
Output is correct |
21 |
Correct |
5 ms |
512 KB |
Output is correct |
22 |
Correct |
5 ms |
384 KB |
Output is correct |
23 |
Correct |
6 ms |
512 KB |
Output is correct |
24 |
Correct |
6 ms |
512 KB |
Output is correct |
25 |
Correct |
5 ms |
512 KB |
Output is correct |
26 |
Correct |
5 ms |
384 KB |
Output is correct |
27 |
Correct |
5 ms |
512 KB |
Output is correct |
28 |
Correct |
5 ms |
384 KB |
Output is correct |
29 |
Correct |
5 ms |
512 KB |
Output is correct |
30 |
Correct |
5 ms |
512 KB |
Output is correct |
31 |
Correct |
6 ms |
512 KB |
Output is correct |
32 |
Correct |
5 ms |
384 KB |
Output is correct |
33 |
Correct |
5 ms |
384 KB |
Output is correct |
34 |
Correct |
303 ms |
23416 KB |
Output is correct |
35 |
Correct |
286 ms |
24112 KB |
Output is correct |
36 |
Correct |
285 ms |
23728 KB |
Output is correct |
37 |
Correct |
320 ms |
24240 KB |
Output is correct |
38 |
Correct |
293 ms |
24324 KB |
Output is correct |
39 |
Correct |
285 ms |
24372 KB |
Output is correct |
40 |
Correct |
307 ms |
25836 KB |
Output is correct |
41 |
Correct |
292 ms |
24752 KB |
Output is correct |
42 |
Correct |
299 ms |
25136 KB |
Output is correct |
43 |
Correct |
333 ms |
25956 KB |
Output is correct |
44 |
Correct |
323 ms |
25940 KB |
Output is correct |
45 |
Correct |
329 ms |
25996 KB |
Output is correct |
46 |
Correct |
322 ms |
26020 KB |
Output is correct |
47 |
Correct |
318 ms |
26136 KB |
Output is correct |
48 |
Correct |
303 ms |
25964 KB |
Output is correct |
49 |
Correct |
294 ms |
25964 KB |
Output is correct |
50 |
Correct |
320 ms |
25968 KB |
Output is correct |
51 |
Correct |
315 ms |
25964 KB |
Output is correct |
52 |
Correct |
185 ms |
26028 KB |
Output is correct |
53 |
Correct |
184 ms |
25964 KB |
Output is correct |
54 |
Correct |
176 ms |
25960 KB |
Output is correct |
55 |
Correct |
177 ms |
25964 KB |
Output is correct |
56 |
Correct |
311 ms |
25964 KB |
Output is correct |
57 |
Correct |
265 ms |
25800 KB |
Output is correct |
58 |
Correct |
262 ms |
25964 KB |
Output is correct |
59 |
Correct |
281 ms |
26100 KB |
Output is correct |
60 |
Correct |
244 ms |
24440 KB |
Output is correct |
61 |
Correct |
265 ms |
25968 KB |
Output is correct |
62 |
Correct |
263 ms |
25580 KB |
Output is correct |
63 |
Correct |
284 ms |
25948 KB |
Output is correct |
64 |
Correct |
277 ms |
25032 KB |
Output is correct |
65 |
Correct |
276 ms |
25964 KB |
Output is correct |