1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
#include <cstdio>
#include <vector>
#include <algorithm>
using namespace std;

typedef pair<int, int> Cmd;

Cmd mydata[3000000 + 9];

int main() {
	int n, m;
	scanf("%d%d", &n, &m);

	for (int i=0; i<n; ++i) mydata[i] = Cmd(i + 1, 0);
	for (int i=0; i<m; ++i) {
		int l, r, k;
		scanf("%d%d%d", &l, &r, &k);
		mydata[n + 2 * i + 0] = Cmd(l, -k);
		mydata[n + 2 * i + 1] = Cmd(r, k);
	}

	n += m * 2;
	sort(mydata, mydata + n);

	int state[4];
	state[1] = state[2] = state[3] = 0;

	int res = 0;

	for (int i=0; i<n; ++i) {
		if (mydata[i].second < 0) ++state[0 - mydata[i].second];
		if (mydata[i].second > 0) --state[0 + mydata[i].second];
		if (mydata[i].second == 0) {
			if (state[1] > 0 && state[2] > 0 && state[3] == 0) ++res;
		}
	}

	printf("%d\n", res);

	return 0;
}