#include<bits/stdc++.h>
using namespace std;
const int MAXN = 100000;
int N, K, Q;
int L[MAXN];
enum {LEFT=0, MID=1, RIGHT=2};
struct Node
{
int l, r, p;
int pos; //position
int h; //height
int pt[3], pd[3]; //parent type, parent distance
} n[2*MAXN+10];
int tp = 0;
int last_left[MAXN], last_right[MAXN];
void build_rec(int id)
{
int from = n[id].l, to = n[id].r, p = id, h = n[id].h;
if(from != -1) last_left[from] = id;
if(to != N) last_right[to] = id;
if(to-from==1) return;
int m_elem = *max_element(L+from+1, L+to);
vector<int> child_ind;
for(int i=from+1; i<=to-1; ++i)
if(L[i] == m_elem) child_ind.push_back(i);
for(int i=0; i<(int)child_ind.size()+1; ++i)
{
n[tp].l = (i==0)?from:child_ind[i-1];
n[tp].r = (i==(int)child_ind.size())?to:child_ind[i];
n[tp].p = p; n[tp].h = h+1; n[tp].pos = i;
for(int t=0; t<3; ++t)
{
int ldist = i; if(t==RIGHT) ++ldist;
int rdist = (int)child_ind.size()-i; if(t==LEFT) ++rdist;
if(ldist < rdist)
n[tp].pt[t] = LEFT, n[tp].pd[t] = ldist;
else if(ldist == rdist)
n[tp].pt[t] = MID, n[tp].pd[t] = ldist;
else
n[tp].pt[t] = RIGHT, n[tp].pd[t] = rdist;
}
build_rec(tp++);
}
}
int calc_dist(int aind, int atype, int bind, int btype)
{
if(aind == bind)
{
if(atype==LEFT&&btype==RIGHT) return 1;
else return 0;
}
int ans1 = n[bind].pos-n[aind].pos-1;
if(atype==LEFT) ++ans1;
if(btype==RIGHT) ++ans1;
if(n[aind].p == 0) return ans1;
return min(ans1,
n[aind].pd[atype] + n[bind].pd[btype] +
(n[aind].pt[atype] == LEFT && n[bind].pt[btype] == RIGHT)
);
}
int dist(int a, int b)
{
if(a>b) swap(a, b);
int aind = last_left[a], atype = LEFT;
int bind = last_right[b], btype = RIGHT;
int dv = 0;
while(n[aind].p != n[bind].p) //until they are sibling rel
{
if(n[aind].h < n[bind].h)
{
//take b parent
int nbind = n[bind].p;
int nbtype = n[bind].pt[btype];
dv += n[bind].pd[btype];
bind = nbind; btype = nbtype;
}
else
{
//take a parent
int naind = n[aind].p;
int natype = n[aind].pt[atype];
dv += n[aind].pd[atype];
aind = naind; atype = natype;
}
}
return calc_dist(aind, atype, bind, btype)+dv;
}
void build()
{
n[tp].l = -1; n[tp].r = N; n[tp].p = -1; n[tp].h = 0;
build_rec(tp++);
}
int main()
{
scanf("%d%d%d", &N, &K, &Q);
for(int i=0; i<N; ++i)
scanf("%d", L+i);
build();
while(Q--)
{
int a, b;
scanf("%d%d", &a, &b);
printf("%d\n", dist(a-1, b-1)-1);
}
}
Compilation message
railway_trip.cpp: In function 'int main()':
railway_trip.cpp:103:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d%d%d", &N, &K, &Q);
~~~~~^~~~~~~~~~~~~~~~~~~~~~
railway_trip.cpp:105:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d", L+i);
~~~~~^~~~~~~~~~~
railway_trip.cpp:110:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d%d", &a, &b);
~~~~~^~~~~~~~~~~~~~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
5 ms |
376 KB |
Output is correct |
2 |
Correct |
6 ms |
376 KB |
Output is correct |
3 |
Correct |
5 ms |
376 KB |
Output is correct |
4 |
Correct |
5 ms |
376 KB |
Output is correct |
5 |
Correct |
5 ms |
376 KB |
Output is correct |
6 |
Correct |
5 ms |
376 KB |
Output is correct |
7 |
Correct |
5 ms |
376 KB |
Output is correct |
8 |
Correct |
5 ms |
376 KB |
Output is correct |
9 |
Correct |
5 ms |
380 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
5 ms |
376 KB |
Output is correct |
2 |
Correct |
31 ms |
9188 KB |
Output is correct |
3 |
Correct |
33 ms |
9592 KB |
Output is correct |
4 |
Correct |
38 ms |
10104 KB |
Output is correct |
5 |
Correct |
36 ms |
10232 KB |
Output is correct |
6 |
Correct |
39 ms |
10488 KB |
Output is correct |
7 |
Correct |
44 ms |
10616 KB |
Output is correct |
8 |
Correct |
21 ms |
6512 KB |
Output is correct |
9 |
Execution timed out |
2072 ms |
2660 KB |
Time limit exceeded |
10 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
123 ms |
11000 KB |
Output is correct |
2 |
Correct |
113 ms |
10872 KB |
Output is correct |
3 |
Correct |
118 ms |
11128 KB |
Output is correct |
4 |
Correct |
120 ms |
11128 KB |
Output is correct |
5 |
Correct |
127 ms |
11256 KB |
Output is correct |
6 |
Correct |
122 ms |
11256 KB |
Output is correct |
7 |
Correct |
113 ms |
11256 KB |
Output is correct |
8 |
Correct |
100 ms |
9120 KB |
Output is correct |
9 |
Correct |
78 ms |
7896 KB |
Output is correct |
10 |
Correct |
88 ms |
7900 KB |
Output is correct |
11 |
Correct |
85 ms |
7896 KB |
Output is correct |
12 |
Correct |
84 ms |
7904 KB |
Output is correct |
13 |
Correct |
84 ms |
7900 KB |
Output is correct |
14 |
Correct |
98 ms |
7804 KB |
Output is correct |
15 |
Correct |
116 ms |
7976 KB |
Output is correct |
16 |
Correct |
113 ms |
8440 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
158 ms |
12152 KB |
Output is correct |
2 |
Correct |
156 ms |
12152 KB |
Output is correct |
3 |
Correct |
153 ms |
12024 KB |
Output is correct |
4 |
Correct |
160 ms |
12176 KB |
Output is correct |
5 |
Correct |
76 ms |
7900 KB |
Output is correct |
6 |
Execution timed out |
2073 ms |
3064 KB |
Time limit exceeded |
7 |
Halted |
0 ms |
0 KB |
- |