//joisc怎麼也有水題阿，雖然我不會，但有猜到梗
#include <bits/stdc++.h>
using namespace std;
#define pii pair<int,int>
#define fs first
#define sc second
int n, a[1110000], b[1110000];
pii dp[1110000][2];
pii dead = {10000000, -10000000};
int main () {
ios_base::sync_with_stdio(false); cin.tie(0);
cin >> n;
for (int i = 1; i <= n * 2; i++) cin >> a[i];
for (int i = 1; i <= n * 2; i++) cin >> b[i];
a[0] = b[0] = -1, dp[0][0] = dp[0][1] = {0, 0};
for (int i = 1; i <= n * 2; i++) dp[i][0] = dp[i][1] = dead;
for (int i = 1; i <= n * 2; i++) {
{
bool y0 = (a[i] >= a[i - 1]) and (dp[i - 1][0] != dead), y1 = (a[i] >= b[i-1]) and (dp[i - 1][1] != dead);
if (y0 and y1) {
dp[i][0] . fs = min(dp[i - 1][0].fs, dp[i - 1][1].fs) + 1;
dp[i][0] . sc = max(dp[i - 1][0].sc, dp[i - 1][1].sc) + 1;
}
else if (y0) dp[i][0] = {dp[i - 1][0].fs + 1, dp[i - 1][0].sc + 1};
else if (y1) dp[i][0] = {dp[i - 1][1].fs + 1, dp[i - 1][1].sc + 1};
}
{
bool y0 = (b[i] >= a[i - 1]) and (dp[i - 1][0] != dead), y1 = (b[i] >= b[i-1]) and (dp[i - 1][1] != dead);
if (y0 and y1) {
dp[i][1] . fs = min(dp[i - 1][0].fs, dp[i - 1][1].fs);
dp[i][1] . sc = max(dp[i - 1][0].sc, dp[i - 1][1].sc);
}
else if (y0) dp[i][1] = dp[i - 1][0];
else if (y1) dp[i][1] = dp[i - 1][1];
}
}
int now = 2;
if (dp[n * 2][0] != dead and dp[n * 2][0].fs <= n and dp[n * 2][0].sc >= n) now = 0;
if (dp[n * 2][1] != dead and dp[n * 2][1].fs <= n and dp[n * 2][1].sc >= n) now = 1;
if (now == 2) {
cout << "-1\n";
return 0;
}
string ans;
int used = 0;
for (int i = n * 2; i >= 1; i--) {
int me = a[i];
if (now == 1) ans += "B", me = b[i];
else ans += "A", used++;
if (dp[i - 1][1] != dead and dp[i - 1][1].fs + used <= n and dp[i - 1][1].sc + used >= n and b[i -1] <= me) now = 1;
else now = 0;
}
reverse(ans.begin(), ans.end());
cout << ans << '\n';
return 0;}
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 2 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 3 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 4 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 5 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 6 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 7 |
Correct |
2 ms |
4444 KB |
Output is correct |
| 8 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 9 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 10 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 11 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 12 |
Correct |
1 ms |
4440 KB |
Output is correct |
| 13 |
Correct |
1 ms |
4440 KB |
Output is correct |
| 14 |
Correct |
1 ms |
4440 KB |
Output is correct |
| 15 |
Correct |
2 ms |
4444 KB |
Output is correct |
| 16 |
Correct |
2 ms |
4444 KB |
Output is correct |
| 17 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 18 |
Correct |
2 ms |
4444 KB |
Output is correct |
| 19 |
Correct |
2 ms |
4444 KB |
Output is correct |
| 20 |
Correct |
1 ms |
4440 KB |
Output is correct |
| 21 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 22 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 23 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 24 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 25 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 26 |
Correct |
1 ms |
4440 KB |
Output is correct |
| 27 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 28 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 29 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 30 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 31 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 32 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 33 |
Correct |
2 ms |
4444 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 2 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 3 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 4 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 5 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 6 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 7 |
Correct |
2 ms |
4444 KB |
Output is correct |
| 8 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 9 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 10 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 11 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 12 |
Correct |
1 ms |
4440 KB |
Output is correct |
| 13 |
Correct |
1 ms |
4440 KB |
Output is correct |
| 14 |
Correct |
1 ms |
4440 KB |
Output is correct |
| 15 |
Correct |
2 ms |
4444 KB |
Output is correct |
| 16 |
Correct |
2 ms |
4444 KB |
Output is correct |
| 17 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 18 |
Correct |
2 ms |
4444 KB |
Output is correct |
| 19 |
Correct |
2 ms |
4444 KB |
Output is correct |
| 20 |
Correct |
1 ms |
4440 KB |
Output is correct |
| 21 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 22 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 23 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 24 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 25 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 26 |
Correct |
1 ms |
4440 KB |
Output is correct |
| 27 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 28 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 29 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 30 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 31 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 32 |
Correct |
1 ms |
4444 KB |
Output is correct |
| 33 |
Correct |
2 ms |
4444 KB |
Output is correct |
| 34 |
Correct |
162 ms |
39876 KB |
Output is correct |
| 35 |
Correct |
168 ms |
43532 KB |
Output is correct |
| 36 |
Correct |
161 ms |
43100 KB |
Output is correct |
| 37 |
Correct |
173 ms |
45724 KB |
Output is correct |
| 38 |
Correct |
148 ms |
45584 KB |
Output is correct |
| 39 |
Correct |
151 ms |
44848 KB |
Output is correct |
| 40 |
Correct |
161 ms |
47040 KB |
Output is correct |
| 41 |
Correct |
156 ms |
45556 KB |
Output is correct |
| 42 |
Correct |
166 ms |
46608 KB |
Output is correct |
| 43 |
Correct |
173 ms |
47176 KB |
Output is correct |
| 44 |
Correct |
180 ms |
47400 KB |
Output is correct |
| 45 |
Correct |
176 ms |
47436 KB |
Output is correct |
| 46 |
Correct |
161 ms |
47436 KB |
Output is correct |
| 47 |
Correct |
162 ms |
46408 KB |
Output is correct |
| 48 |
Correct |
157 ms |
46312 KB |
Output is correct |
| 49 |
Correct |
176 ms |
47136 KB |
Output is correct |
| 50 |
Correct |
178 ms |
46508 KB |
Output is correct |
| 51 |
Correct |
184 ms |
46704 KB |
Output is correct |
| 52 |
Correct |
121 ms |
35688 KB |
Output is correct |
| 53 |
Correct |
128 ms |
35656 KB |
Output is correct |
| 54 |
Correct |
109 ms |
35660 KB |
Output is correct |
| 55 |
Correct |
113 ms |
35368 KB |
Output is correct |
| 56 |
Correct |
168 ms |
47596 KB |
Output is correct |
| 57 |
Correct |
172 ms |
42572 KB |
Output is correct |
| 58 |
Correct |
149 ms |
42572 KB |
Output is correct |
| 59 |
Correct |
145 ms |
42568 KB |
Output is correct |
| 60 |
Correct |
144 ms |
41856 KB |
Output is correct |
| 61 |
Correct |
143 ms |
43084 KB |
Output is correct |
| 62 |
Correct |
145 ms |
43304 KB |
Output is correct |
| 63 |
Correct |
143 ms |
42060 KB |
Output is correct |
| 64 |
Correct |
145 ms |
42644 KB |
Output is correct |
| 65 |
Correct |
145 ms |
43148 KB |
Output is correct |
