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
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
#include <cstdio>
#include <vector>

struct CoverTree {
#define nr (wp + wk + 1) >> 1
    std::vector<unsigned> el;
    int s,p,k,color;

    CoverTree(int size) {
        s = (1<<(size+1));
        el.resize(s);
    }

    void Add(int p1,int k1, int color1) {
        p = p1;
        k = k1;
        color = color1;
        Mark(0, s/2, 1);
    }

    unsigned Get(int p1) {
        unsigned result = 0;
        int g = (s/2) + p1;

        while (g>0) {
            result = result | el[g];
            g /= 2;
        }

        return result;
    }


private:
    void Mark(int wp, int wk, int g) {
        if (k<=wp || p>=wk) {
            return;
        }

        if (p<=wp && k>=wk) {
            el[g] = el[g] | (1U << color);
        } else {
            Mark(wp,nr,2*g);
            Mark(nr,wk,2*g+1);
        }
    }
};


int main() {
    CoverTree ctree(20);
    int N,M;
    scanf("%d %d", &N, &M);

    for (int i=0; i<M; ++i) {
        int l,p,k;
        scanf("%d %d %d",&l,&p,&k);
        ctree.Add(l,p+1,k);
    }

    int result = 0;
    for (int i=1; i<=N; ++i) {
        if (ctree.Get(i) == 6) {
            result++;
        }
    }

    printf("%d\n", result);
    return 0;
}