#include<bits/stdc++.h>
using namespace std;
const int nmax=5e5+42;
int n;
int a[2*nmax],b[2*nmax];
string current;
pair<int,int> dp[2*nmax][2];
pair<int,int> my_merge(pair<int,int> u,pair<int,int> v)
{
//cout<<"my_merge "<<u.first<<" "<<u.second<<" "<<v.first<<" "<<v.second<<endl;
if(u.first>u.second)return v;
if(v.first>v.second)return u;
return {min(u.first,v.first),max(u.second,v.second)};
}
bool inside(pair<int,int> cur,int val)
{
return cur.first<=val&&val<=cur.second;
}
int main()
{
scanf("%i",&n);
for(int i=1;i<=2*n;i++)scanf("%i",&a[i]);
for(int i=1;i<=2*n;i++)scanf("%i",&b[i]);
for(int pos=0;pos<=2*n;pos++)
for(int side=0;side<2;side++)
dp[pos][side]={1,0};
dp[0][0]={0,0};
for(int pos=1;pos<=2*n;pos++)
for(int side=0;side<2;side++)
{
if(side==0)
{
if(a[pos-1]<=a[pos])dp[pos][side]=my_merge(dp[pos][side],dp[pos-1][0]);
if(b[pos-1]<=a[pos])dp[pos][side]=my_merge(dp[pos][side],dp[pos-1][1]);
if(dp[pos][side].first<=dp[pos][side].second)dp[pos][side].first++,dp[pos][side].second++;
}
else
{
if(a[pos-1]<=b[pos])dp[pos][side]=my_merge(dp[pos][side],dp[pos-1][0]);
if(b[pos-1]<=b[pos])dp[pos][side]=my_merge(dp[pos][side],dp[pos-1][1]);
}
dp[pos][side].second=min(dp[pos][side].second,n);
dp[pos][side].first=max(dp[pos][side].first,pos-n);
//cout<<pos<<" "<<side<<" -> "<<dp[pos][side].first<<" "<<dp[pos][side].second<<endl;
}
int pos=2*n,a_now=n,side=0;
if(dp[2*n][0].first<=dp[2*n][0].second);
else if(dp[2*n][1].first<=dp[2*n][1].second)side=1;
else {printf("-1\n");return 0;}
while(pos)
{
current.push_back('A'+side);
if(side==0)
{
a_now--;
if(a[pos-1]<=a[pos]&&inside(dp[pos-1][0],a_now))side=0;
else side=1;
}
else
{
if(a[pos-1]<=b[pos]&&inside(dp[pos-1][0],a_now))side=0;
else side=1;
}
pos--;
}
reverse(current.begin(),current.end());
for(int i=0;i<2*n;i++)
printf("%c",current[i]);
printf("\n");
return 0;
}
Compilation message
building4.cpp: In function 'int main()':
building4.cpp:28:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%i",&n);
~~~~~^~~~~~~~~
building4.cpp:30:33: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
for(int i=1;i<=2*n;i++)scanf("%i",&a[i]);
~~~~~^~~~~~~~~~~~
building4.cpp:31:33: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
for(int i=1;i<=2*n;i++)scanf("%i",&b[i]);
~~~~~^~~~~~~~~~~~
| # |
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 |
5 ms |
384 KB |
Output is correct |
| 4 |
Correct |
5 ms |
384 KB |
Output is correct |
| 5 |
Correct |
6 ms |
512 KB |
Output is correct |
| 6 |
Correct |
6 ms |
384 KB |
Output is correct |
| 7 |
Correct |
6 ms |
384 KB |
Output is correct |
| 8 |
Correct |
6 ms |
512 KB |
Output is correct |
| 9 |
Correct |
6 ms |
384 KB |
Output is correct |
| 10 |
Correct |
6 ms |
384 KB |
Output is correct |
| 11 |
Correct |
6 ms |
512 KB |
Output is correct |
| 12 |
Correct |
6 ms |
384 KB |
Output is correct |
| 13 |
Correct |
6 ms |
512 KB |
Output is correct |
| 14 |
Correct |
6 ms |
512 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 |
384 KB |
Output is correct |
| 18 |
Correct |
6 ms |
512 KB |
Output is correct |
| 19 |
Correct |
6 ms |
384 KB |
Output is correct |
| 20 |
Correct |
7 ms |
512 KB |
Output is correct |
| 21 |
Correct |
6 ms |
384 KB |
Output is correct |
| 22 |
Correct |
7 ms |
512 KB |
Output is correct |
| 23 |
Correct |
7 ms |
384 KB |
Output is correct |
| 24 |
Correct |
6 ms |
512 KB |
Output is correct |
| 25 |
Correct |
6 ms |
512 KB |
Output is correct |
| 26 |
Correct |
6 ms |
384 KB |
Output is correct |
| 27 |
Correct |
6 ms |
512 KB |
Output is correct |
| 28 |
Correct |
7 ms |
384 KB |
Output is correct |
| 29 |
Correct |
6 ms |
384 KB |
Output is correct |
| 30 |
Correct |
6 ms |
512 KB |
Output is correct |
| 31 |
Correct |
6 ms |
512 KB |
Output is correct |
| 32 |
Correct |
6 ms |
384 KB |
Output is correct |
| 33 |
Correct |
6 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 |
5 ms |
384 KB |
Output is correct |
| 4 |
Correct |
5 ms |
384 KB |
Output is correct |
| 5 |
Correct |
6 ms |
512 KB |
Output is correct |
| 6 |
Correct |
6 ms |
384 KB |
Output is correct |
| 7 |
Correct |
6 ms |
384 KB |
Output is correct |
| 8 |
Correct |
6 ms |
512 KB |
Output is correct |
| 9 |
Correct |
6 ms |
384 KB |
Output is correct |
| 10 |
Correct |
6 ms |
384 KB |
Output is correct |
| 11 |
Correct |
6 ms |
512 KB |
Output is correct |
| 12 |
Correct |
6 ms |
384 KB |
Output is correct |
| 13 |
Correct |
6 ms |
512 KB |
Output is correct |
| 14 |
Correct |
6 ms |
512 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 |
384 KB |
Output is correct |
| 18 |
Correct |
6 ms |
512 KB |
Output is correct |
| 19 |
Correct |
6 ms |
384 KB |
Output is correct |
| 20 |
Correct |
7 ms |
512 KB |
Output is correct |
| 21 |
Correct |
6 ms |
384 KB |
Output is correct |
| 22 |
Correct |
7 ms |
512 KB |
Output is correct |
| 23 |
Correct |
7 ms |
384 KB |
Output is correct |
| 24 |
Correct |
6 ms |
512 KB |
Output is correct |
| 25 |
Correct |
6 ms |
512 KB |
Output is correct |
| 26 |
Correct |
6 ms |
384 KB |
Output is correct |
| 27 |
Correct |
6 ms |
512 KB |
Output is correct |
| 28 |
Correct |
7 ms |
384 KB |
Output is correct |
| 29 |
Correct |
6 ms |
384 KB |
Output is correct |
| 30 |
Correct |
6 ms |
512 KB |
Output is correct |
| 31 |
Correct |
6 ms |
512 KB |
Output is correct |
| 32 |
Correct |
6 ms |
384 KB |
Output is correct |
| 33 |
Correct |
6 ms |
384 KB |
Output is correct |
| 34 |
Correct |
424 ms |
23788 KB |
Output is correct |
| 35 |
Correct |
441 ms |
42028 KB |
Output is correct |
| 36 |
Correct |
437 ms |
41520 KB |
Output is correct |
| 37 |
Correct |
437 ms |
42256 KB |
Output is correct |
| 38 |
Correct |
406 ms |
42412 KB |
Output is correct |
| 39 |
Correct |
416 ms |
41508 KB |
Output is correct |
| 40 |
Correct |
430 ms |
44776 KB |
Output is correct |
| 41 |
Correct |
377 ms |
42496 KB |
Output is correct |
| 42 |
Correct |
445 ms |
44080 KB |
Output is correct |
| 43 |
Correct |
471 ms |
45416 KB |
Output is correct |
| 44 |
Correct |
466 ms |
45544 KB |
Output is correct |
| 45 |
Correct |
467 ms |
45288 KB |
Output is correct |
| 46 |
Correct |
443 ms |
45348 KB |
Output is correct |
| 47 |
Correct |
428 ms |
44520 KB |
Output is correct |
| 48 |
Correct |
413 ms |
44296 KB |
Output is correct |
| 49 |
Correct |
442 ms |
45028 KB |
Output is correct |
| 50 |
Correct |
460 ms |
44520 KB |
Output is correct |
| 51 |
Correct |
454 ms |
44520 KB |
Output is correct |
| 52 |
Correct |
344 ms |
33512 KB |
Output is correct |
| 53 |
Correct |
334 ms |
33640 KB |
Output is correct |
| 54 |
Correct |
323 ms |
33640 KB |
Output is correct |
| 55 |
Correct |
320 ms |
33256 KB |
Output is correct |
| 56 |
Correct |
432 ms |
45464 KB |
Output is correct |
| 57 |
Correct |
375 ms |
40300 KB |
Output is correct |
| 58 |
Correct |
365 ms |
40532 KB |
Output is correct |
| 59 |
Correct |
374 ms |
40568 KB |
Output is correct |
| 60 |
Correct |
361 ms |
38700 KB |
Output is correct |
| 61 |
Correct |
380 ms |
41128 KB |
Output is correct |
| 62 |
Correct |
374 ms |
40552 KB |
Output is correct |
| 63 |
Correct |
383 ms |
40936 KB |
Output is correct |
| 64 |
Correct |
364 ms |
39600 KB |
Output is correct |
| 65 |
Correct |
379 ms |
40940 KB |
Output is correct |
