結果

提出番号	1819
提出者	TangentDay
言語	C++
提出日時	2018-08-04 14:05:06
問題名	(73)観光計画
結果	AC
点数	100%

---

テストケース

ソースコード

#include <iostream>
#include <fstream>
#include <cstdio>
#include <cmath>
#include <vector>
#include <cstring>
#include <string>
#include <set>
#include <map>
#include <stack>
#include <queue>
#include <deque>
#include <bitset>
#include <algorithm>
#include <complex>
using namespace std;
 
#define REP(i,n) for(int i=0; i<n; ++i)
#define FOR(i,a,b) for(int i=a; i<=b; ++i)
#define FORR(i,a,b) for (int i=a; i>=b; --i)
#define ALL(c) (c).begin(), (c).end()
 
typedef long long ll;
typedef vector<int> VI;
typedef vector<ll> VL;
typedef vector<VL> VVL;
typedef vector<VI> VVI;
typedef pair<int,int> P;
typedef pair<ll,ll> PL;

int in() { int x; scanf("%d", &x); return x; }
ll lin() { ll x; scanf("%lld", &x); return x; }

struct edge{ll to,cost;};
const ll INF = 1e16;

int main() {
    int n, m, k;
    cin >> n >> m >> k;

    vector<vector<edge> > graph(n);
    REP(i,m){
        int a = in() - 1, b = in() - 1, c = in();
        graph[a].push_back(edge{b, c});
        graph[b].push_back(edge{a, c});
    }

    VL d(n, INF);
    priority_queue<PL, vector<PL>, greater<PL> > q;
    REP(i,k){
        int x = in() - 1, y = in();
        d[x] = -y;
        q.push(make_pair(-y, x));
    }
    while (!q.empty()){
        PL a = q.top();
        q.pop();
        int now = a.second;
        if(d[now] < a.first) continue;
        REP(i,graph[now].size()){
            edge e = graph[now][i];
            int next = e.to;
            if (d[next] > d[now] + e.cost){
                d[next] = d[now] + e.cost;
                q.push(make_pair(d[next], next));
            }
        }
    }

    int ans = 0;
    REP(i,n) if (d[i] <= 0) ans++;
    cout << ans << endl;

    return 0;
}