#include <bits/stdc++.h>
#define pb push_back
#define f first
#define sc second
using namespace std;
typedef long long int ll;
typedef string str;
const int inf = 1e9 + 9;
bool inside(pair<int, int> a, int p){
return (p >= a.f && p <= a.sc);
}
int main(){
ios_base::sync_with_stdio(0);
cin.tie(0);
int n; cin >> n;
vector<int> a(2*n), b(2*n);
for(int &x: a) cin >> x;
for(int &x: b) cin >> x;
vector<pair<int, int>> dpa(2*n), dpb(2*n);
dpa[0] = {1, 1};
dpb[0] = {0, 0};
for(int i = 1; i < 2*n; i++){
auto [al, ar] = dpa[i-1];
auto [bl, br] = dpb[i-1];
{
int l1 = -1, r1 = -1, l2 = -1, r2 = -1;
if(a[i] >= a[i-1] && al != -1) l1 = al+1, r1 = ar+1;
if(a[i] >= b[i-1] && bl != -1) l2 = bl+1, r2 = br+1;
if(l1 == -1 && l2 == -1){
dpa[i] = {-1, -1};
}
else if(l1 == -1){
dpa[i] = {l2, r2};
}
else if(l2 == -1){
dpa[i] = {l1, r1};
}
else{
if(l1 > l2) swap(l1, l2), swap(r1, r2);
dpa[i] = {min(l1, l2), max(r1, r2)};
}
}
{
int l1 = -1, r1 = -1, l2 = -1, r2 = -1;
if(b[i] >= a[i-1] && al != -1) l1 = al, r1 = ar;
if(b[i] >= b[i-1] && bl != -1) l2 = bl, r2 = br;
if(l1 == -1 && l2 == -1){
dpb[i] = {-1, -1};
}
else if(l1 == -1){
dpb[i] = {l2, r2};
}
else if(l2 == -1){
dpb[i] = {l1, r1};
}
else{
if(l1 > l2) swap(l1, l2), swap(r1, r2);
dpb[i] = {min(l1, l2), max(r1, r2)};
}
}
}
if(!inside(dpa[2*n-1], n) && !inside(dpb[2*n-1], n)){
cout << "-1\n";
exit(0);
}
str ans = "";
str cur;
if(inside(dpa[2*n-1], n)) cur = "A";
else cur = "B";
int cnt = n;
for(int i = 2*n-1; i >= 0; i--){
ans+=cur;
if(cur == "A") cnt--;
if(i > 0){
if(inside(dpa[i-1], cnt) && (cur == "A" ? a:b)[i] >= a[i-1]) cur = "A";
else cur = "B";
}
}
reverse(ans.begin(), ans.end());
cout << ans << "\n";
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
492 KB |
Output is correct |
2 |
Correct |
1 ms |
364 KB |
Output is correct |
3 |
Correct |
1 ms |
364 KB |
Output is correct |
4 |
Correct |
1 ms |
364 KB |
Output is correct |
5 |
Correct |
2 ms |
492 KB |
Output is correct |
6 |
Correct |
2 ms |
492 KB |
Output is correct |
7 |
Correct |
2 ms |
492 KB |
Output is correct |
8 |
Correct |
2 ms |
492 KB |
Output is correct |
9 |
Correct |
2 ms |
492 KB |
Output is correct |
10 |
Correct |
1 ms |
492 KB |
Output is correct |
11 |
Correct |
2 ms |
492 KB |
Output is correct |
12 |
Correct |
2 ms |
492 KB |
Output is correct |
13 |
Correct |
2 ms |
492 KB |
Output is correct |
14 |
Correct |
2 ms |
492 KB |
Output is correct |
15 |
Correct |
2 ms |
492 KB |
Output is correct |
16 |
Correct |
2 ms |
492 KB |
Output is correct |
17 |
Correct |
2 ms |
492 KB |
Output is correct |
18 |
Correct |
2 ms |
492 KB |
Output is correct |
19 |
Correct |
2 ms |
492 KB |
Output is correct |
20 |
Correct |
1 ms |
492 KB |
Output is correct |
21 |
Correct |
2 ms |
492 KB |
Output is correct |
22 |
Correct |
2 ms |
492 KB |
Output is correct |
23 |
Correct |
2 ms |
492 KB |
Output is correct |
24 |
Correct |
2 ms |
492 KB |
Output is correct |
25 |
Correct |
2 ms |
512 KB |
Output is correct |
26 |
Correct |
2 ms |
492 KB |
Output is correct |
27 |
Correct |
2 ms |
492 KB |
Output is correct |
28 |
Correct |
2 ms |
492 KB |
Output is correct |
29 |
Correct |
2 ms |
492 KB |
Output is correct |
30 |
Correct |
2 ms |
492 KB |
Output is correct |
31 |
Correct |
2 ms |
492 KB |
Output is correct |
32 |
Correct |
1 ms |
492 KB |
Output is correct |
33 |
Correct |
2 ms |
492 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
492 KB |
Output is correct |
2 |
Correct |
1 ms |
364 KB |
Output is correct |
3 |
Correct |
1 ms |
364 KB |
Output is correct |
4 |
Correct |
1 ms |
364 KB |
Output is correct |
5 |
Correct |
2 ms |
492 KB |
Output is correct |
6 |
Correct |
2 ms |
492 KB |
Output is correct |
7 |
Correct |
2 ms |
492 KB |
Output is correct |
8 |
Correct |
2 ms |
492 KB |
Output is correct |
9 |
Correct |
2 ms |
492 KB |
Output is correct |
10 |
Correct |
1 ms |
492 KB |
Output is correct |
11 |
Correct |
2 ms |
492 KB |
Output is correct |
12 |
Correct |
2 ms |
492 KB |
Output is correct |
13 |
Correct |
2 ms |
492 KB |
Output is correct |
14 |
Correct |
2 ms |
492 KB |
Output is correct |
15 |
Correct |
2 ms |
492 KB |
Output is correct |
16 |
Correct |
2 ms |
492 KB |
Output is correct |
17 |
Correct |
2 ms |
492 KB |
Output is correct |
18 |
Correct |
2 ms |
492 KB |
Output is correct |
19 |
Correct |
2 ms |
492 KB |
Output is correct |
20 |
Correct |
1 ms |
492 KB |
Output is correct |
21 |
Correct |
2 ms |
492 KB |
Output is correct |
22 |
Correct |
2 ms |
492 KB |
Output is correct |
23 |
Correct |
2 ms |
492 KB |
Output is correct |
24 |
Correct |
2 ms |
492 KB |
Output is correct |
25 |
Correct |
2 ms |
512 KB |
Output is correct |
26 |
Correct |
2 ms |
492 KB |
Output is correct |
27 |
Correct |
2 ms |
492 KB |
Output is correct |
28 |
Correct |
2 ms |
492 KB |
Output is correct |
29 |
Correct |
2 ms |
492 KB |
Output is correct |
30 |
Correct |
2 ms |
492 KB |
Output is correct |
31 |
Correct |
2 ms |
492 KB |
Output is correct |
32 |
Correct |
1 ms |
492 KB |
Output is correct |
33 |
Correct |
2 ms |
492 KB |
Output is correct |
34 |
Correct |
243 ms |
23532 KB |
Output is correct |
35 |
Correct |
278 ms |
42020 KB |
Output is correct |
36 |
Correct |
270 ms |
41380 KB |
Output is correct |
37 |
Correct |
280 ms |
42148 KB |
Output is correct |
38 |
Correct |
259 ms |
42148 KB |
Output is correct |
39 |
Correct |
263 ms |
37796 KB |
Output is correct |
40 |
Correct |
283 ms |
33120 KB |
Output is correct |
41 |
Correct |
261 ms |
42308 KB |
Output is correct |
42 |
Correct |
280 ms |
43428 KB |
Output is correct |
43 |
Correct |
290 ms |
29356 KB |
Output is correct |
44 |
Correct |
289 ms |
29308 KB |
Output is correct |
45 |
Correct |
285 ms |
29280 KB |
Output is correct |
46 |
Correct |
279 ms |
38112 KB |
Output is correct |
47 |
Correct |
286 ms |
44384 KB |
Output is correct |
48 |
Correct |
283 ms |
44128 KB |
Output is correct |
49 |
Correct |
278 ms |
32352 KB |
Output is correct |
50 |
Correct |
294 ms |
44512 KB |
Output is correct |
51 |
Correct |
291 ms |
44512 KB |
Output is correct |
52 |
Correct |
211 ms |
33632 KB |
Output is correct |
53 |
Correct |
211 ms |
33632 KB |
Output is correct |
54 |
Correct |
222 ms |
33632 KB |
Output is correct |
55 |
Correct |
200 ms |
33376 KB |
Output is correct |
56 |
Correct |
270 ms |
30432 KB |
Output is correct |
57 |
Correct |
244 ms |
40288 KB |
Output is correct |
58 |
Correct |
243 ms |
40544 KB |
Output is correct |
59 |
Correct |
245 ms |
40568 KB |
Output is correct |
60 |
Correct |
234 ms |
38436 KB |
Output is correct |
61 |
Correct |
254 ms |
41056 KB |
Output is correct |
62 |
Correct |
243 ms |
40416 KB |
Output is correct |
63 |
Correct |
312 ms |
40928 KB |
Output is correct |
64 |
Correct |
244 ms |
39716 KB |
Output is correct |
65 |
Correct |
255 ms |
41056 KB |
Output is correct |