Submission #9284

#	Time	Username	Problem	Language	Result	Execution time	Memory
9284		Yoon	Your life (kriii2_Y)	C++98	0 / 4	0 ms	3580 KiB

Y

#include <stdio.h>
#include <vector>
#include <queue>
using namespace std;
int N,M;
vector< pair<int,int> > adj[100010];
vector<int> dijkstra(int src)
{
	vector<int> dist(N+1,1234567890);
	dist[src]=0;
	priority_queue< pair<int,int> > pq;
	pq.push(make_pair(0,src));
	while(!pq.empty()){
		int cost=-pq.top().first;
		int here=pq.top().second;
		pq.pop();
		if(dist[here]<cost)continue;
		for(int i=0;i<adj[here].size();++i){
			int there=adj[here][i].first;
			int nextDist=cost+adj[here][i].second;
			if(dist[there]>nextDist){
				dist[there]=nextDist;
				pq.push(make_pair(-nextDist,there));
			}
		}
	}
	return dist;
}
int main()
{
	int i,a,b;
	scanf("%d %d",&N,&M);
	for(i=1;i<=M;i++){
		scanf("%d %d",&a,&b);
		adj[a].push_back(make_pair(b,1));
	}
	vector<int> shortest=dijkstra(1);
	int ret=shortest[N];
	if(ret==1234567899)printf("-1\n");
	else printf("%d\n",ret);
	
	return 0;
}

• Subtask 1: 0 / 1
• Subtask 2: 0 / 3