Submission #792666

# Submission time Handle Problem Language Result Execution time Memory
792666 2023-07-25T07:58:39 Z GEN 이지후(#10086) Line Town (CCO23_day1problem3) C++17
0 / 25
1 ms 212 KB
#include <bits/stdc++.h>
using namespace std;
using lint = long long;
using pi = array<lint, 2>;
#define sz(v) ((int)(v).size())
#define all(v) (v).begin(), (v).end()
const int MAXN = 500005;

struct bit {
	int tree[MAXN];
	void add(int x, int v) {
		for (int i = x + 2; i < MAXN; i += i & -i)
			tree[i] += v;
	}
	int query(int x) {
		int ret = 0;
		for (int i = x + 2; i; i -= i & -i)
			ret += tree[i];
		return ret;
	}
} bit;

int main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	int n;
	cin >> n;
	vector<pi> a(n);
	for (int i = 0; i < n; i++) {
		cin >> a[i][0];
		a[i][1] = i;
		if (i & 1)
			a[i][0] *= -1;
	}
	sort(all(a), [&](const pi &p, const pi &q) { return abs(p[0]) < abs(q[0]); });
	bool ok = 1;
	for (int i = 0; i < n - 1; i++) {
		if (i % 2 == 0 && a[i][0] + a[i + 1][0] > 0)
			ok = 0;
		if (i % 2 == 1 && a[i][0] + a[i + 1][0] < 0)
			ok = 0;
	}
	if (ok == 0) {
		cout << "-1\n";
		return 0;
	}
	lint ret = 0;
	for (int i = n - 1; i >= 0; i--) {
		bit.add(a[i][1], 1);
		ret += bit.query(a[i][1] - 1);
	}
	cout << ret << "\n";
}
# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Incorrect 0 ms 212 KB Output isn't correct
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Incorrect 0 ms 212 KB Output isn't correct
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Incorrect 0 ms 212 KB Output isn't correct
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Incorrect 0 ms 212 KB Output isn't correct
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Incorrect 0 ms 212 KB Output isn't correct
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Incorrect 0 ms 212 KB Output isn't correct
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Incorrect 0 ms 212 KB Output isn't correct
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Incorrect 0 ms 212 KB Output isn't correct
3 Halted 0 ms 0 KB -