#include <bits/stdc++.h>
using namespace std;
int const N = 5e5 + 50;
int bucket_size = 0, n, q;
int v[N], M[N];
struct queries{
int x, y, id, ans;
};
queries Q[N];
bool cmp(queries a, queries b){
return (a.x / bucket_size) < (b.x / bucket_size) || ((a.x / bucket_size) == (b.x / bucket_size) && a.y <= b.y);
}
bool cmp_id(queries a, queries b){
return a.id <= b.id;
}
int main()
{
cin >> n >> q;
for(int i = 1; i <= n; ++i)
cin >> v[i];
for(int i = 1; i <= q; ++i)
{
cin >> Q[i].x >> Q[i].y;
Q[i].id = i;
}
bucket_size = (int) (n / sqrt(q));
sort(Q + 1, Q + q + 1, cmp);
int l = 0, r = 0, ans = 0;
for(int i = 1; i <= q; ++i)
{
while(r < Q[i].y)
{
++r;
++M[v[r]];
if(M[v[r]] == 2) ++ans;
if(M[v[r]] == 3) --ans;
}
while(l > Q[i].x)
{
--l;
++M[v[l]];
if(M[v[l]] == 2) ++ans;
if(M[v[l]] == 3) --ans;
}
while(r > Q[i].y)
{
--M[v[r]];
if(M[v[r]] == 2) ++ans;
if(M[v[r]] == 1) --ans;
--r;
}
while(l < Q[i].x)
{
--M[v[l]];
if(M[v[l]] == 2) ++ans;
if(M[v[l]] == 1) --ans;
++l;
}
Q[i].ans = ans;
}
sort(Q + 1, Q + q + 1, cmp_id);
for(int i = 1; i <= q; ++i)
cout << Q[i].ans << "\n";
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
2396 KB |
Output is correct |
2 |
Correct |
1 ms |
2396 KB |
Output is correct |
3 |
Correct |
1 ms |
2396 KB |
Output is correct |
4 |
Correct |
5 ms |
2396 KB |
Output is correct |
5 |
Correct |
140 ms |
4696 KB |
Output is correct |
6 |
Correct |
146 ms |
4704 KB |
Output is correct |
7 |
Correct |
329 ms |
7132 KB |
Output is correct |
8 |
Correct |
543 ms |
9808 KB |
Output is correct |
9 |
Correct |
776 ms |
10472 KB |
Output is correct |
10 |
Correct |
1032 ms |
13400 KB |
Output is correct |