#include<bits/stdc++.h>
#pragma GCC optimize(2)
using namespace std;
int n, m, cnt, ccnt, head[100005], nxt[400005], to[400005], w[400005], d[100005];
map<pair<int, pair<int, int>>, int> ma;
struct node {
	int a, b, c, num, ans;
} b[100005], c[100005];
int ans[200005];
bool comp1(node p, node q) {
	return (p.a == q.a) ? (p.b == q.b ? p.c < q.c : p.b < q.b) : (p.a < q.a);
}
bool comp2(node p, node q) {
	return (p.b == q.b ? p.c < q.c : p.b < q.b);
}
int a[10000007];
inline int lowbit(int p) {
	return p & -p;
}
inline void add(int p, int q) {
	while (p <= m) {
		a[p] += q;
		p += lowbit(p);
	}
}
inline int query(int p) {
	int ccnt = 0;
	while (p >= 1) {
		ccnt += a[p];
		p -= lowbit(p);
	}
	return ccnt;
}
void solve(int l, int r) {
	if (l == r) return;
	int mid = (l + r) >> 1;
	solve(l, mid);
	solve(mid + 1, r);
	sort(c + l, c + mid + 1, comp2);
	sort(c + mid + 1, c + r + 1, comp2);
	int ll = l, rr = mid + 1;
	for (rr = mid + 1; rr <= r; rr++) {
		while (ll <= mid && c[ll].b <= c[rr].b) {
			add(c[ll].c, c[ll].num);
			ll++;
		}
		c[rr].ans += query(c[rr].c);
	}
	for (int i = l; i <= ll - 1; i++) {
		add(c[i].c, -c[i].num);
	}
}
inline void dijkstra(int s) {
	memset(d, 0x3f, sizeof(d));
	priority_queue<pair<int, int>, vector<pair<int, int>>, greater<pair<int, int>>> que;
	que.push(make_pair(0, s));
	d[s] = 0;
	int ct = 0;
	while (que.size()) {
		pair<int, int> u = que.top();
		que.pop();
		if (d[u.second] != u.first) continue;
//		cout << u.first << " " << u.second << " " << (++ct) << "\n";
		for (int i = head[u.second]; i; i = nxt[i]) {
			if (d[to[i]] > u.first + w[i]) {
				d[to[i]] = u.first + w[i];
				que.push(make_pair(d[to[i]], to[i]));
			}
		}
	}
}
inline void add(int p, int q, int ww) {
	nxt[++ccnt] = head[p];
	to[ccnt] = q;
	head[p] = ccnt;
	w[ccnt] = ww;
}
signed main() {
	ios::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	cin >> n >> m;
	int p, q, ww;
	for (int i = 1; i <= m; i++) {
		cin >> p >> q >> ww;
		add(p, q, ww), add(q, p, ww);
	}
	dijkstra(1);
	int maxn = 0;
	for (int i = 1; i <= n; i++) {
		b[i].a = d[i] + 1;
		maxn = max(maxn, d[i] + 1);
	}
	dijkstra(2);
	for (int i = 1; i <= n; i++) {
		b[i].b = d[i] + 1;
		maxn = max(maxn, d[i] + 1);
	}
	dijkstra(3);
	for (int i = 1; i <= n; i++) {
		b[i].c = d[i] + 1;
		maxn = max(maxn, d[i] + 1);
		ma[make_pair(b[i].a, make_pair(b[i].b, b[i].c))]++;
//		cout << i << " " << b[i].a << " " << b[i].b << ' ' << b[i].c << "\n";
	}
	sort(b + 1, b + n + 1, comp1);
	m = 10000001;
	int op = 1;
	for (int i = 2; i <= n + 1; i++) {
		if (b[i].a != b[i - 1].a || b[i].b != b[i - 1].b || b[i].c != b[i - 1].c) {
			c[++cnt] = b[i - 1];
			c[cnt].num = op;
			op = 1;
		} else {
			op++;
		}
	}
	solve(1, cnt);
	int aans = 0;
	for (int i = 1; i <= n; i++) {
		if (c[i].ans == 0) aans += c[i].num;
	}
	cout << aans;
}