Dijkstra + priority_queue

模版

EOJ 最短路：http://acm.cs.ecnu.edu.cn/problem.php?problemid=1817

#include <cstdio>#include <deque>#include <set>#include <string>#include <map>#include <vector>#include <cstring>#include <iostream>#include <algorithm>#include <cmath>#include <queue>using namespace std;typedef long long LL;#define Debug(x) (cerr << #x << " = " << (x) << endl)#define Debug2(x, y) (cerr << #x << " = " << (x) << ", " << #y << " = " << (y) << endl)template<class T> inline T& RD(T &x){      char c; for (c = getchar(); c < '0'; c = getchar()); x = c - '0'; for (c = getchar(); '0' <= c && c <= '9'; c = getchar()) x = x * 10 + c - '0';      return x;  }const int inf = 0x3f3f3f3f;const int maxn = 1001;//vector<int> g[maxn];int g[maxn][maxn];bool used[maxn];int dist[maxn];priority_queue<pair<int,int>, vector<pair<int,int> > ,greater<pair<int,int> > > q;int Dijkstra(int s,int e){memset(used,false,sizeof(used));memset(dist,0x3f,sizeof(dist));while(!q.empty())q.pop();dist[s] = 0;q.push(make_pair(0,s));while(!q.empty()){int u = q.top().second;int tt = q.top().first;if(u == e){return tt;}q.pop();if(used[u] == false){used[u] = true;for(int v=1;v<=e;v++){if(!used[v] && dist[u]+g[u][v] < dist[v]){dist[v] = dist[u] + g[u][v];q.push(make_pair(dist[v],v));}}}}return dist[e];}int main(){//Dijkstra(1);int n,m;while(~scanf("%d%d",&n,&m)){memset(g,0x3f,sizeof(g));for(int i=0;i<m;i++){int a,b,c;scanf("%d%d%d",&a,&b,&c);g[a][b] = c;}int ans = Dijkstra(1,n);if(ans >= inf)ans = -1;printf("%d\n", ans);}}