Dijstra单源最短路【模板】（裸的，邻接矩阵）
例题：洛谷-热浪
附：最详细的讲解
代码：
#include <iostream>
#include <cstdio>
using namespace std;
const int inf = 1e9 + 7;
const int N = 2357;
int n,m,s,e[N][N],dis[N],u,v,w;
bool vis[N];
int main()
{
scanf("%d%d%d",&n,&m,&s);
for(int i = 1; i <= n; i ++)
for(int j = 1; j <= n; j ++)
if(i != j)e[i][j] = inf;
for(int i = 1; i <= m; i ++)
{
scanf("%d%d%d",&u,&v,&w);
e[u][v] = min(e[u][v],w);
}
for(int i = 1; i <= n; i ++)
dis[i] = e[s][i];
vis[s] = 1;
for(int i = 1; i < n; i ++)
{
int minn = inf;
for(int j = 1; j <= n; j ++)
{
if(dis[j] < minn && vis[j] == 0)
{
minn = dis[j];
u = j;
}
}
vis[u] = 1;
for(v = 1; v <= n; v ++)
dis[v] = min(dis[v],dis[u]+e[u][v]);
}
for(int i = 1; i <= n; i ++)
printf("%d ",dis[i]);
return 0;
}