백준 1753 최단경로 / C++

#include<stdio.h>
#include<algorithm>
#include<vector>
#include<queue>
using namespace std;
#define INF 1e9
int n,m;
int start;
vector < pair<int, int>>v[20001];
vector<int> dijkstra(int start)
{
	vector<int>dist(n + 1, INF);
	priority_queue<pair<int, int>>pq;
	dist[start] = 0;
	pq.push({ 0,start });
	while (!pq.empty())
	{
		int cost = -pq.top().first;
		int now = pq.top().second;
		pq.pop();
		if (dist[now] < cost)
			continue;
		for (auto& next : v[now])
		{
			int nv = next.first;
			int nw = cost + next.second;
			if (dist[nv] > nw)
			{
				dist[nv] = nw;
				pq.push({ -nw,nv });
			}
		}
	}
	return dist;
}
int main()
{
	scanf("%d %d %d", &n, &m, &start);
	for (int i = 0; i < m; i++)
	{
		int s, e, c;
		scanf("%d %d %d", &s, &e, &c);
		v[s].push_back({ e,c });
	}
	vector<int> result = dijkstra(start);
	for (int i = 1; i <= n; i++)
	{
		if (result[i] == INF)
		{
			printf("INF\n");
			continue;
		}
		printf("%d\n", result[i]);
	}
}