#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
const int MN = 200010;
int N;
pii P[MN];
int A[MN];
vector<int> X, Y;
unordered_map<int, int> dx, dy;
void add(int x, int v, vector<pii> &stk) {
while(!stk.empty() && stk.back().first > v) stk.pop_back();
stk.push_back(pii(v, x));
}
struct BIT {
vector<vector<pii> > tree;
void init() {
tree = vector<vector<pii> >(4 * N);
}
void upd(int x, int v, int l, int r, int n) {
if(x < l || r < x) return;
add(v, x, tree[n]);
if(l == r) return;
int m = (l + r)>>1;
upd(x, v, l, m, 2*n);
upd(x, v, m + 1, r, 2*n + 1);
}
int quer(int a, int b, int &v, int l, int r, int n) {
if(b < l || r < a) return 0;
if(a <= l && r <= b) {
int s = 0, e = (int)tree[n].size() - 1, p = (int)tree[n].size();
while(s <= e) {
int m = (s + e)>>1;
if(tree[n][m].second < v) {
p = m;
e = m - 1;
}
else s = m + 1;
}
if(p != tree[n].size()) v = tree[n].back().second;
return (int)tree[n].size() - p;
}
int m = (l + r)>>1;
int L = quer(a, b, v, l, m, 2*n);
int R = quer(a, b, v, m + 1, r, 2*n + 1);
return L + R;
}
} bit;
int main() {
scanf("%d", &N);
for(int i = 0; i < N; i++) {
scanf("%d %d", &P[i].first, &P[i].second);
X.push_back(P[i].first);
Y.push_back(P[i].second);
}
sort(X.begin(), X.end());
sort(Y.begin(), Y.end());
X.resize(unique(X.begin(), X.end()) - X.begin());
Y.resize(unique(Y.begin(), Y.end()) - Y.begin());
for(int i = 0; i < N; i++) {
dx[X[i]] = i;
dy[Y[i]] = i;
}
for(int i = 0; i < N; i++) {
P[i].first = dx[P[i].first];
P[i].second = dy[P[i].second];
A[ P[i].first ] = P[i].second;
}
ll ans = 0;
bit.init();
for(int i = N - 1; i >= 0; i--) {
int t = N;
ans += bit.quer(A[i], N - 1, t, 0, N - 1, 1);
bit.upd(A[i], i, 0, N - 1, 1);
}
printf("%lld", ans);
}
Compilation message
scarecrows.cpp: In member function 'int BIT::quer(int, int, int&, int, int, int)':
scarecrows.cpp:46:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
if(p != tree[n].size()) v = tree[n].back().second;
~~^~~~~~~~~~~~~~~~~
scarecrows.cpp: In function 'int main()':
scarecrows.cpp:57:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d", &N);
~~~~~^~~~~~~~~~
scarecrows.cpp:60:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d %d", &P[i].first, &P[i].second);
~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
512 KB |
Output is correct |
2 |
Correct |
2 ms |
512 KB |
Output is correct |
3 |
Correct |
2 ms |
512 KB |
Output is correct |
4 |
Correct |
2 ms |
384 KB |
Output is correct |
5 |
Correct |
2 ms |
512 KB |
Output is correct |
6 |
Correct |
2 ms |
512 KB |
Output is correct |
7 |
Correct |
3 ms |
512 KB |
Output is correct |
8 |
Correct |
2 ms |
512 KB |
Output is correct |
9 |
Correct |
3 ms |
512 KB |
Output is correct |
10 |
Correct |
3 ms |
384 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
9 ms |
2304 KB |
Output is correct |
2 |
Correct |
11 ms |
1664 KB |
Output is correct |
3 |
Correct |
10 ms |
1920 KB |
Output is correct |
4 |
Correct |
8 ms |
1664 KB |
Output is correct |
5 |
Correct |
10 ms |
1664 KB |
Output is correct |
6 |
Correct |
10 ms |
1664 KB |
Output is correct |
7 |
Correct |
11 ms |
1664 KB |
Output is correct |
8 |
Correct |
10 ms |
2304 KB |
Output is correct |
9 |
Correct |
10 ms |
1792 KB |
Output is correct |
10 |
Correct |
10 ms |
1792 KB |
Output is correct |
11 |
Correct |
11 ms |
1664 KB |
Output is correct |
12 |
Correct |
9 ms |
1664 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
398 ms |
81260 KB |
Output is correct |
2 |
Correct |
896 ms |
53736 KB |
Output is correct |
3 |
Correct |
604 ms |
66144 KB |
Output is correct |
4 |
Correct |
484 ms |
51604 KB |
Output is correct |
5 |
Correct |
642 ms |
52168 KB |
Output is correct |
6 |
Correct |
728 ms |
53052 KB |
Output is correct |
7 |
Correct |
775 ms |
53504 KB |
Output is correct |
8 |
Correct |
777 ms |
53448 KB |
Output is correct |
9 |
Correct |
588 ms |
82044 KB |
Output is correct |
10 |
Correct |
641 ms |
60532 KB |
Output is correct |
11 |
Correct |
738 ms |
55212 KB |
Output is correct |
12 |
Correct |
803 ms |
53964 KB |
Output is correct |
13 |
Correct |
818 ms |
53660 KB |
Output is correct |
14 |
Correct |
572 ms |
81476 KB |
Output is correct |
15 |
Correct |
742 ms |
55364 KB |
Output is correct |
16 |
Correct |
795 ms |
53704 KB |
Output is correct |
17 |
Correct |
467 ms |
37780 KB |
Output is correct |
18 |
Correct |
717 ms |
53580 KB |
Output is correct |
19 |
Correct |
674 ms |
53588 KB |
Output is correct |
20 |
Correct |
700 ms |
53704 KB |
Output is correct |