#include<bits/stdc++.h>
#include<fstream>
using namespace std;
#define sz(a) (int)a.size()
#define ALL(v) v.begin(), v.end()
#define ALLR(v) v.rbegin(), v.rend()
#define ll long long
#define pb push_back
#define forr(i, a, b) for(int i = a; i < b; i++)
#define dorr(i, a, b) for(int i = a; i >= b; i--)
#define ld long double
#define vt vector
#include<fstream>
#define fi first
#define se second
#define pll pair<ll, ll>
#define pii pair<int, int>
#define mpp make_pair
const ld PI = 3.14159265359, prec = 1e-9;;
//using u128 = __uint128_t;
//const int x[4] = {1, 0, -1, 0};
//const int y[4] = {0, -1, 0, 1};
const ll mod = 1e9 + 7, pr = 31;
const int mxn = 1e6 + 5, mxq = 1e5 + 5, sq = 500, mxv = 5e4 + 1;
//const int base = (1 <<18);
const ll inf = 1e9 + 5, neg = -69420, inf2 = 1e14;
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
// have fun!
int n;
int mx[mxn + 1][2], mn[mxn + 1][2], a[mxn + 1], b[mxn + 1];
void ckmin(int &a, int b){
if(a > b)a = b;
}
void ckmax(int &a, int b){
if(a < b)a = b;
}
void solve(){
cin >> n;
for(int i = 1; i <= 2 * n; i++)cin >> a[i];
for(int i = 1; i <= 2 * n; i++)cin >> b[i];
for(int i = 1; i <= 2 * n; i++){
mn[i][0] = mn[i][1] = inf; mx[i][0] = mx[i][1] = 0;
}
//minimum and maximum Bs
mn[1][0] = mx[1][0] = 0; mn[1][1] = mx[1][1] = 1;
for(int i = 1; i < 2 * n; i++){
if(a[i] <= a[i + 1]){
ckmin(mn[i + 1][0], mn[i][0]); ckmax(mx[i + 1][0], mx[i][0]);
}if(a[i] <= b[i + 1]){
ckmin(mn[i + 1][1], mn[i][0] + 1); ckmax(mx[i + 1][1], mx[i][0] + 1);
}if(b[i] <= a[i + 1]){
ckmin(mn[i + 1][0], mn[i][1]); ckmax(mx[i + 1][0], mx[i][1]);
}if(b[i] <= b[i + 1]){
ckmin(mn[i + 1][1], mn[i][1] + 1); ckmax(mx[i + 1][1], mx[i][1] + 1);
}
}
int id = 2 * n, type;
if(mx[2 * n][0] >= n && mn[2 * n][0] <= n)type = 0;
else if(mx[2 * n][1] >= n && mn[2 * n][1] <= n)type = 1;
else{
cout << -1; return;
}
int taken = 0;
string ans = "";
while(1){
ans += ((type == 0) ? 'A' : 'B');
if(id == 1)break;
taken += type;
int v = ((type == 0) ? a[id] : b[id]);
if(a[id - 1] <= v && mx[id - 1][0] + taken >= n && mn[id - 1][0] + taken <= n)type = 0;
else if(b[id - 1] <= v && mx[id - 1][1] + taken >= n && mn[id - 1][1] + taken <= n)type = 1;
id--;
}
reverse(ALL(ans));
cout << ans;
}
signed main(){
ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
//freopen("DATA.inp", "r", stdin);
//freopen("DATA.out", "w", stdout);
int tt; tt = 1;
while(tt--){
solve();
}
return(0);
}
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
6492 KB |
Output is correct |
| 2 |
Correct |
1 ms |
6488 KB |
Output is correct |
| 3 |
Correct |
1 ms |
6488 KB |
Output is correct |
| 4 |
Correct |
1 ms |
6492 KB |
Output is correct |
| 5 |
Correct |
2 ms |
6492 KB |
Output is correct |
| 6 |
Correct |
1 ms |
6492 KB |
Output is correct |
| 7 |
Correct |
2 ms |
6492 KB |
Output is correct |
| 8 |
Correct |
2 ms |
6492 KB |
Output is correct |
| 9 |
Correct |
1 ms |
6492 KB |
Output is correct |
| 10 |
Correct |
2 ms |
6492 KB |
Output is correct |
| 11 |
Correct |
3 ms |
6488 KB |
Output is correct |
| 12 |
Correct |
2 ms |
6492 KB |
Output is correct |
| 13 |
Correct |
3 ms |
6492 KB |
Output is correct |
| 14 |
Correct |
2 ms |
6492 KB |
Output is correct |
| 15 |
Correct |
2 ms |
6492 KB |
Output is correct |
| 16 |
Correct |
1 ms |
6692 KB |
Output is correct |
| 17 |
Correct |
2 ms |
6748 KB |
Output is correct |
| 18 |
Correct |
2 ms |
6492 KB |
Output is correct |
| 19 |
Correct |
2 ms |
6492 KB |
Output is correct |
| 20 |
Correct |
2 ms |
6488 KB |
Output is correct |
| 21 |
Correct |
2 ms |
6492 KB |
Output is correct |
| 22 |
Correct |
2 ms |
6492 KB |
Output is correct |
| 23 |
Correct |
1 ms |
6492 KB |
Output is correct |
| 24 |
Correct |
2 ms |
6492 KB |
Output is correct |
| 25 |
Correct |
1 ms |
6488 KB |
Output is correct |
| 26 |
Correct |
2 ms |
6656 KB |
Output is correct |
| 27 |
Correct |
2 ms |
6492 KB |
Output is correct |
| 28 |
Correct |
2 ms |
6492 KB |
Output is correct |
| 29 |
Correct |
1 ms |
6492 KB |
Output is correct |
| 30 |
Correct |
2 ms |
6644 KB |
Output is correct |
| 31 |
Correct |
2 ms |
6492 KB |
Output is correct |
| 32 |
Correct |
2 ms |
6492 KB |
Output is correct |
| 33 |
Correct |
1 ms |
6492 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
1 ms |
6492 KB |
Output is correct |
| 2 |
Correct |
1 ms |
6488 KB |
Output is correct |
| 3 |
Correct |
1 ms |
6488 KB |
Output is correct |
| 4 |
Correct |
1 ms |
6492 KB |
Output is correct |
| 5 |
Correct |
2 ms |
6492 KB |
Output is correct |
| 6 |
Correct |
1 ms |
6492 KB |
Output is correct |
| 7 |
Correct |
2 ms |
6492 KB |
Output is correct |
| 8 |
Correct |
2 ms |
6492 KB |
Output is correct |
| 9 |
Correct |
1 ms |
6492 KB |
Output is correct |
| 10 |
Correct |
2 ms |
6492 KB |
Output is correct |
| 11 |
Correct |
3 ms |
6488 KB |
Output is correct |
| 12 |
Correct |
2 ms |
6492 KB |
Output is correct |
| 13 |
Correct |
3 ms |
6492 KB |
Output is correct |
| 14 |
Correct |
2 ms |
6492 KB |
Output is correct |
| 15 |
Correct |
2 ms |
6492 KB |
Output is correct |
| 16 |
Correct |
1 ms |
6692 KB |
Output is correct |
| 17 |
Correct |
2 ms |
6748 KB |
Output is correct |
| 18 |
Correct |
2 ms |
6492 KB |
Output is correct |
| 19 |
Correct |
2 ms |
6492 KB |
Output is correct |
| 20 |
Correct |
2 ms |
6488 KB |
Output is correct |
| 21 |
Correct |
2 ms |
6492 KB |
Output is correct |
| 22 |
Correct |
2 ms |
6492 KB |
Output is correct |
| 23 |
Correct |
1 ms |
6492 KB |
Output is correct |
| 24 |
Correct |
2 ms |
6492 KB |
Output is correct |
| 25 |
Correct |
1 ms |
6488 KB |
Output is correct |
| 26 |
Correct |
2 ms |
6656 KB |
Output is correct |
| 27 |
Correct |
2 ms |
6492 KB |
Output is correct |
| 28 |
Correct |
2 ms |
6492 KB |
Output is correct |
| 29 |
Correct |
1 ms |
6492 KB |
Output is correct |
| 30 |
Correct |
2 ms |
6644 KB |
Output is correct |
| 31 |
Correct |
2 ms |
6492 KB |
Output is correct |
| 32 |
Correct |
2 ms |
6492 KB |
Output is correct |
| 33 |
Correct |
1 ms |
6492 KB |
Output is correct |
| 34 |
Correct |
179 ms |
42736 KB |
Output is correct |
| 35 |
Correct |
162 ms |
43220 KB |
Output is correct |
| 36 |
Correct |
181 ms |
42764 KB |
Output is correct |
| 37 |
Correct |
167 ms |
43276 KB |
Output is correct |
| 38 |
Correct |
161 ms |
43268 KB |
Output is correct |
| 39 |
Correct |
181 ms |
42376 KB |
Output is correct |
| 40 |
Correct |
171 ms |
45000 KB |
Output is correct |
| 41 |
Correct |
175 ms |
43136 KB |
Output is correct |
| 42 |
Correct |
172 ms |
44368 KB |
Output is correct |
| 43 |
Correct |
209 ms |
45200 KB |
Output is correct |
| 44 |
Correct |
207 ms |
45328 KB |
Output is correct |
| 45 |
Correct |
191 ms |
45328 KB |
Output is correct |
| 46 |
Correct |
166 ms |
45200 KB |
Output is correct |
| 47 |
Correct |
174 ms |
44352 KB |
Output is correct |
| 48 |
Correct |
172 ms |
44216 KB |
Output is correct |
| 49 |
Correct |
176 ms |
45016 KB |
Output is correct |
| 50 |
Correct |
202 ms |
44476 KB |
Output is correct |
| 51 |
Correct |
204 ms |
44420 KB |
Output is correct |
| 52 |
Correct |
121 ms |
33596 KB |
Output is correct |
| 53 |
Correct |
121 ms |
33520 KB |
Output is correct |
| 54 |
Correct |
118 ms |
33592 KB |
Output is correct |
| 55 |
Correct |
108 ms |
33332 KB |
Output is correct |
| 56 |
Correct |
184 ms |
45504 KB |
Output is correct |
| 57 |
Correct |
141 ms |
40376 KB |
Output is correct |
| 58 |
Correct |
140 ms |
40712 KB |
Output is correct |
| 59 |
Correct |
161 ms |
40588 KB |
Output is correct |
| 60 |
Correct |
143 ms |
39440 KB |
Output is correct |
| 61 |
Correct |
145 ms |
41032 KB |
Output is correct |
| 62 |
Correct |
158 ms |
40776 KB |
Output is correct |
| 63 |
Correct |
147 ms |
41096 KB |
Output is correct |
| 64 |
Correct |
154 ms |
40016 KB |
Output is correct |
| 65 |
Correct |
147 ms |
41080 KB |
Output is correct |
