#include<stdio.h>
#include<string.h>
#include<stdlib.h>
#include<algorithm>
using namespace std;
int n;
int p,t=1,a[600010],ch[600010],top,q[2500010],s[600010],e[600010],dap[600010],f,r,treeb[2500010],treef[2500010],tree[2500010];
void update(int x,int gap)
{
int s=x+t-1;
tree[s]=gap;
s/=2;
while(s>0){
tree[s]=max(tree[s*2],tree[s*2+1]);
s/=2;
}
}
void updatef(int x,int gap)
{
int s=x+t-1;
treef[s]=gap;
s/=2;
while(s>0){
treef[s]=min(treef[s*2],treef[s*2+1]);
s/=2;
}
}
void updateb(int x,int gap)
{
int s=x+t-1;
treeb[s]=gap;
s/=2;
while(s>0){
treeb[s]=max(treeb[s*2],treeb[s*2+1]);
s/=2;
}
}
int queryf(int x,int y,int k,int s,int e)
{
if(s>e) return 2147483647;
if(s<=x && y<=e) return treef[k];
if(s>y || e<x) return 2147483647;
return min(queryf(x,(x+y)/2,k*2,s,e),queryf((x+y)/2+1,y,k*2+1,s,e));
}
int queryb(int x,int y,int k,int s,int e)
{
if(s>e) return 0;
if(s<=x && y<=e) return treeb[k];
if(s>y || e<x) return 0;
return max(queryb(x,(x+y)/2,k*2,s,e),queryb((x+y)/2+1,y,k*2+1,s,e));
}
int query(int x,int y,int k,int s,int e)
{
if(s>e) return 0;
if(s<=x && y<=e) return tree[k];
if(s>y || e<x) return 0;
return max(query(x,(x+y)/2,k*2,s,e),query((x+y)/2+1,y,k*2+1,s,e));
}
void check()
{
int i;
//1
for(i=1;i<=n;i++){
if(dap[i]==1) update(s[i],e[i]);
}
for(i=1;i<=n;i++){
if(dap[i]==1)
{
if(query(1,t,1,s[i]+1,e[i]-1)>e[i]){printf("IMPOSSIBLE"); exit(0);}
}
}
memset(tree,0,sizeof tree);
//0
for(i=1;i<=n;i++){
if(dap[i]==0) update(s[i],e[i]);
}
for(i=1;i<=n;i++){
if(dap[i]==0)
{
if(query(1,t,1,s[i]+1,e[i]-1)>e[i]){printf("IMPOSSIBLE"); exit(0);}
}
}
}
int main()
{
int i;
scanf("%d",&n);
for(i=1;i<=n*2;i++)
{
scanf("%d",&a[i]);
if(s[a[i]]==0) s[a[i]]=i;
else e[a[i]]=i;
}
for(i=1;;i++){if(t>=n*2) break; t*=2;}
for(i=1;i<=t*2;i++) treef[i]=2147483647;
for(i=1;i<=n;i++)
{
updatef(e[i],s[i]);
updateb(s[i],e[i]);
}
for(i=1;i<=n;i++)
{
if(ch[i]==0)
{
ch[i]=1;
dap[i]=1;
q[++r]=i;
updatef(e[i],2147483647);
updateb(s[i],0);
while(f!=r)
{
f++;
for(;;)
{
p=queryf(1,t,1,s[q[f]]+1,e[q[f]]-1);
if(p>=s[q[f]]) break;
updatef(e[a[p]],2147483647);
updateb(s[a[p]],0);
dap[a[p]]=(dap[q[f]]+1)%2;
ch[a[p]]=1;
q[++r]=a[p];
}
for(;;)
{
p=queryb(1,t,1,s[q[f]]+1,e[q[f]]-1);
if(p<=e[q[f]]) break;
updateb(s[a[p]],0);
updatef(e[a[p]],2147483647);
dap[a[p]]=(dap[q[f]]+1)%2;
ch[a[p]]=1;
q[++r]=a[p];
}
}
}
}
check();
for(i=1;i<=n*2;i++)
{
if(dap[a[i]]==0) printf("v");
else printf("^");
}
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
51872 KB |
Output is correct |
2 |
Correct |
0 ms |
51872 KB |
Output is correct |
3 |
Correct |
0 ms |
51872 KB |
Output is correct |
4 |
Correct |
0 ms |
51872 KB |
Output is correct |
5 |
Correct |
0 ms |
51872 KB |
Output is correct |
6 |
Correct |
0 ms |
51872 KB |
Output is correct |
7 |
Correct |
0 ms |
51872 KB |
Output is correct |
8 |
Correct |
0 ms |
51872 KB |
Output is correct |
9 |
Correct |
0 ms |
51872 KB |
Output is correct |
10 |
Correct |
0 ms |
51872 KB |
Output is correct |
11 |
Correct |
0 ms |
51872 KB |
Output is correct |
12 |
Correct |
0 ms |
51872 KB |
Output is correct |
13 |
Correct |
0 ms |
51872 KB |
Output is correct |
14 |
Correct |
0 ms |
51872 KB |
Output is correct |
15 |
Correct |
0 ms |
51872 KB |
Output is correct |
16 |
Correct |
0 ms |
51872 KB |
Output is correct |
17 |
Correct |
0 ms |
51872 KB |
Output is correct |
18 |
Correct |
0 ms |
51872 KB |
Output is correct |
19 |
Correct |
0 ms |
51872 KB |
Output is correct |
20 |
Correct |
0 ms |
51872 KB |
Output is correct |
21 |
Correct |
0 ms |
51872 KB |
Output is correct |
22 |
Correct |
0 ms |
51872 KB |
Output is correct |
23 |
Correct |
0 ms |
51872 KB |
Output is correct |
24 |
Correct |
0 ms |
51872 KB |
Output is correct |
25 |
Correct |
0 ms |
51872 KB |
Output is correct |
26 |
Correct |
0 ms |
51872 KB |
Output is correct |
27 |
Correct |
0 ms |
51872 KB |
Output is correct |
28 |
Correct |
0 ms |
51872 KB |
Output is correct |
29 |
Correct |
0 ms |
51872 KB |
Output is correct |
30 |
Correct |
4 ms |
51872 KB |
Output is correct |
31 |
Correct |
0 ms |
51872 KB |
Output is correct |
32 |
Correct |
0 ms |
51872 KB |
Output is correct |
33 |
Correct |
0 ms |
51872 KB |
Output is correct |
34 |
Correct |
0 ms |
51872 KB |
Output is correct |
35 |
Correct |
0 ms |
51872 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
51872 KB |
Output is correct |
2 |
Correct |
0 ms |
51872 KB |
Output is correct |
3 |
Correct |
0 ms |
51872 KB |
Output is correct |
4 |
Correct |
0 ms |
51872 KB |
Output is correct |
5 |
Correct |
0 ms |
51872 KB |
Output is correct |
6 |
Correct |
0 ms |
51872 KB |
Output is correct |
7 |
Correct |
0 ms |
51872 KB |
Output is correct |
8 |
Correct |
0 ms |
51872 KB |
Output is correct |
9 |
Correct |
0 ms |
51872 KB |
Output is correct |
10 |
Correct |
4 ms |
51872 KB |
Output is correct |
11 |
Correct |
0 ms |
51872 KB |
Output is correct |
12 |
Correct |
0 ms |
51872 KB |
Output is correct |
13 |
Correct |
4 ms |
51872 KB |
Output is correct |
14 |
Correct |
0 ms |
51872 KB |
Output is correct |
15 |
Correct |
4 ms |
51872 KB |
Output is correct |
16 |
Correct |
0 ms |
51872 KB |
Output is correct |
17 |
Correct |
0 ms |
51872 KB |
Output is correct |
18 |
Correct |
0 ms |
51872 KB |
Output is correct |
19 |
Correct |
4 ms |
51872 KB |
Output is correct |
20 |
Correct |
0 ms |
51872 KB |
Output is correct |
21 |
Correct |
0 ms |
51872 KB |
Output is correct |
22 |
Correct |
0 ms |
51872 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
20 ms |
51872 KB |
Output is correct |
2 |
Correct |
20 ms |
51872 KB |
Output is correct |
3 |
Correct |
108 ms |
51872 KB |
Output is correct |
4 |
Correct |
140 ms |
51872 KB |
Output is correct |
5 |
Correct |
120 ms |
51872 KB |
Output is correct |
6 |
Correct |
104 ms |
51872 KB |
Output is correct |
7 |
Correct |
140 ms |
51872 KB |
Output is correct |
8 |
Correct |
4 ms |
51872 KB |
Output is correct |
9 |
Correct |
20 ms |
51872 KB |
Output is correct |
10 |
Correct |
104 ms |
51872 KB |
Output is correct |
11 |
Correct |
100 ms |
51872 KB |
Output is correct |
12 |
Correct |
108 ms |
51872 KB |
Output is correct |
13 |
Correct |
104 ms |
51872 KB |
Output is correct |
14 |
Correct |
124 ms |
51872 KB |
Output is correct |
15 |
Correct |
148 ms |
51872 KB |
Output is correct |
16 |
Correct |
24 ms |
51872 KB |
Output is correct |
17 |
Correct |
28 ms |
51872 KB |
Output is correct |
18 |
Correct |
124 ms |
51872 KB |
Output is correct |
19 |
Correct |
96 ms |
51872 KB |
Output is correct |
20 |
Correct |
176 ms |
51872 KB |
Output is correct |
21 |
Correct |
152 ms |
51872 KB |
Output is correct |
22 |
Correct |
152 ms |
51872 KB |
Output is correct |
23 |
Correct |
196 ms |
51872 KB |
Output is correct |
24 |
Correct |
212 ms |
51872 KB |
Output is correct |
25 |
Correct |
200 ms |
51872 KB |
Output is correct |
26 |
Correct |
164 ms |
51872 KB |
Output is correct |
27 |
Correct |
296 ms |
51872 KB |
Output is correct |
28 |
Correct |
296 ms |
51872 KB |
Output is correct |
29 |
Correct |
304 ms |
51872 KB |
Output is correct |
30 |
Correct |
304 ms |
51872 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
280 ms |
51872 KB |
Output is correct |
2 |
Correct |
516 ms |
51872 KB |
Output is correct |
3 |
Correct |
316 ms |
51872 KB |
Output is correct |
4 |
Correct |
488 ms |
51872 KB |
Output is correct |
5 |
Correct |
544 ms |
51872 KB |
Output is correct |
6 |
Correct |
684 ms |
51872 KB |
Output is correct |
7 |
Correct |
800 ms |
51872 KB |
Output is correct |
8 |
Correct |
604 ms |
51872 KB |
Output is correct |
9 |
Correct |
384 ms |
51872 KB |
Output is correct |
10 |
Correct |
332 ms |
51872 KB |
Output is correct |
11 |
Correct |
432 ms |
51872 KB |
Output is correct |
12 |
Correct |
408 ms |
51872 KB |
Output is correct |
13 |
Correct |
788 ms |
51872 KB |
Output is correct |
14 |
Correct |
632 ms |
51872 KB |
Output is correct |
15 |
Correct |
344 ms |
51872 KB |
Output is correct |
16 |
Correct |
356 ms |
51872 KB |
Output is correct |
17 |
Correct |
400 ms |
51872 KB |
Output is correct |
18 |
Correct |
368 ms |
51872 KB |
Output is correct |
19 |
Correct |
564 ms |
51872 KB |
Output is correct |
20 |
Correct |
812 ms |
51872 KB |
Output is correct |
21 |
Correct |
772 ms |
51872 KB |
Output is correct |
22 |
Execution timed out |
1000 ms |
51872 KB |
Program timed out |
23 |
Halted |
0 ms |
0 KB |
- |