CF449B T了第五组

#include<iostream>
#include<vector>
#include<queue>
#include<string.h> 
using namespace std;
struct aa {
	int v;
	int val;
	const bool operator < (const aa &r) const {return val >r.val;}
};
int zdl[100010] = {};
bool vis[100010] = {};
vector<aa> ve[100010] = {};
bool lian[100010] = {};
int last[100010] = {};
priority_queue<pair<int, int> > q;
int ans = 0;
int n = 0;
int m = 0;
int k = 0;
void dijistra() {
	memset(zdl,0x3f3f3f3f,sizeof(zdl));
	priority_queue<aa> q;
	zdl[1] = 0;
	q.push({1, 0});
	while(!q.empty()) {
		aa nn = q.top();
		q.pop();
		vis[nn.v] = true;
		for (auto vv : ve[nn.v]) {
			if(zdl[vv.v] >= nn.val + vv.val) {
				if(lian[vv.v] && nn.v != 1) {
					ans++;
					lian[vv.v] = false;
				}
				zdl[vv.v] = nn.val + vv.val;
				if(!vis[vv.v]) {
					q.push({vv.v, zdl[vv.v]});
				}
			}
		}
	}
}
int main() {
//	freopen("test.in", "r", stdin);
//	freopen("test.out", "w", stdout);
	cin >> n >> m >> k;
	memset(last,0x3f3f3f3f,sizeof(last));
	for (int i = 0; i < m; ++i) {
		int u = 0;
		int v = 0;
		int z = 0;
		cin >> u >> v >> z;
		if(u == 1) {
			last[v] = min(last[v], z);
		}
		if(v == 1){
			last[u] = min(last[u], z);
		}
		ve[u].push_back({v, z});
		ve[v].push_back({u, z});
	}
	for (int i = 0; i < k; ++i) {
		int s = 0;
		int z = 0;
		cin >> s >> z;
		if(lian[s] || last[s] <= z) {
			ans++;
		}
		if (last[s] > z) {
			lian[s] = true;
			last[s] = z;
			ve[1].push_back({s, z});
			ve[s].push_back({1, z});
		}
		 
	}
	dijistra();
	cout << ans;
	return 0;
}