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//标程Dijkstra #include<iostream> #include<algorithm> #include<vector> using namespace std; //T int n = 60, m, vis[1010]; //Graph struct Edge{ int v, w; Edge(int v, int w):v(v),w(w){} }; vector<Edge>G[70]; //Dijkstra int dis[70], book[70], s = (int)'Z'-'A'; void Dijkstra(){ for(int i = 0; i < n; i++)dis[i] = 0xffffff; for(int i = 0; i < G[s].size(); i++)//bugs数据可能有覆盖 dis[G[s][i].v] = min(dis[G[s][i].v],G[s][i].w); dis[s] = 0; book[s] = 1; for(int i = 0; i < n; i++){ int v, w=0xffffff; for(int j = 0; j < n; j++) if(!book[j] && dis[j]<w) w = dis[v=j]; book[v] = 1; for(int j = 0; j < G[v].size(); j++) dis[G[v][j].v] = min(dis[G[v][j].v], w+G[v][j].w); } } int main(){ cin>>m; for(int i = 1; i <= m; i++){ char a, b; int w; cin>>a>>b>>w; int x = a-'A', y = b-'A'; if(x>=0 && x<25)vis[x] = 1; if(y>=0 && y<25)vis[y] = 1; G[x].push_back(Edge(y,w)); G[y].push_back(Edge(x,w)); } Dijkstra(); int v, w=0xffffff; for(int i = 0; i < n; i++) if(vis[i] && dis[i]<w) w = dis[v=i]; cout<<(char)(v+'A')<<" "<<w<<"\n"; return 0; }//数据太小, Floyd一番水 #include<iostream> #include<algorithm> using namespace std; int n = 60, m; int e[1010][1010], vis[1010]; int main(){ cin>>m; for(int i = 0; i < n; i++) for(int j = 0; j < n; j++) e[i][j] = i==j ? 0 : 0xffffff; for(int i = 0; i < m; i++){ char a, b; int w; cin>>a>>b>>w; int x = a-'A', y = b-'A'; if(x>=0 && x<25)vis[x] = 1; if(y>=0 && y<25)vis[y] = 1; //bugs数据可能有覆盖 e[x][y] = min(e[x][y], w); e[y][x] = min(e[y][x], w); } for(int k = 0; k < n; k++) for(int i = 0; i < n; i++) for(int j = 0; j < n; j++) e[i][j] = min(e[i][j], e[i][k]+e[j][k]); int ans2 = 0xffffff, ans1; for(int i = 0; i < n; i++)if(vis[i] && e[i][(int)'Z'-'A']<ans2){ ans2 = e[i][(int)'Z'-'A']; ans1 = i; } cout<<(char)(ans1+'A')<<" "<<ans2; return 0; } 文章来源: 【codevs1079】回家