SPFA
#include<cstring> #include<cstdio> #include<queue> using namespace std; const int maxn=1e6+10; const int maxm=2*maxn; struct Edge{ int u,v,w; }edge[maxm]; int head[maxn],cnt; inline void add(int u,int v,int w){edge[++cnt].u=head[u],edge[cnt].v=v,edge[cnt].w=w,head[u]=cnt;} int dis[maxn],vis[maxn]; queue<int>q; int n,m; inline void spfa(int s) { memset(dis,0x7f,sizeof(dis)); memset(vis,0,sizeof(vis)); dis[s]=0,vis[s]=1,q.push(s); while(!q.empty()) { int cur=q.front();q.pop(),vis[cur]=0; for(int i=head[cur];i;i=edge[i].u) { int v=edge[i].v; if(dis[v]>dis[cur]+edge[i].w) { dis[v]=dis[cur]+edge[i].w; if(!vis[v])vis[v]=1,q.push(v); } } } printf("Shortest Paths from point %d are: ",s); for(int i=1;i<=n;i++)printf("%d ",dis[i]); puts(""); } int main() { int u,v,w; scanf("%d%d",&n,&m); while(m--)scanf("%d%d%d",&u,&v,&w),add(u,v,w),add(v,u,w); for(int i=1;i<=n;i++)spfa(i); return 0; }