Submission #17,453

2025-07-17 11:11:08

cpp17

Accepted 75/75

39ms

4176 KiB

#include <bits/stdc++.h>
using namespace std;

int main() {

	ios_base::sync_with_stdio(false);
	cin.tie(0);

	int n, m; cin >> n >> m;
	vector<int> v(n+1, 0);
	for (int i = 0; i < m; i++) {
		int a, b; cin >> a >> b;
		v[a]++; v[b]--;
	}

	int ans = 0;
	for (int i = 1; i <= n; i++) {
		v[i] += v[max(0, i-1)];
		if (v[i] == 0 && i < n) {
            ans++;
        }
	}
	cout << ans;

	return 0;
}

	Sum	Test	Verdict		Time	Memory
base	75/75
		1	Accepted	0/0	1ms	316 KiB
		2	Accepted	0/0	39ms	4148 KiB
		3	Accepted	3/3	1ms	316 KiB
		4	Accepted	3/3	1ms	316 KiB
		5	Accepted	3/3	1ms	316 KiB
		6	Accepted	3/3	1ms	316 KiB
		7	Accepted	3/3	1ms	316 KiB
		8	Accepted	4/4	1ms	316 KiB
		9	Accepted	4/4	1ms	316 KiB
		10	Accepted	4/4	1ms	552 KiB
		11	Accepted	4/4	1ms	564 KiB
		12	Accepted	4/4	1ms	564 KiB
		13	Accepted	4/4	3ms	564 KiB
		14	Accepted	4/4	4ms	1076 KiB
		15	Accepted	4/4	3ms	1268 KiB
		16	Accepted	4/4	4ms	1780 KiB
		17	Accepted	4/4	4ms	1844 KiB
		18	Accepted	4/4	6ms	2356 KiB
		19	Accepted	4/4	4ms	1844 KiB
		20	Accepted	4/4	6ms	2356 KiB
		21	Accepted	4/4	28ms	4148 KiB
		22	Accepted	4/4	29ms	4176 KiB