原题链接：https://www.luogu.org/problemnew/show/1078#sub
今天想写图论。
气得要死，在洛谷一直都是60，说我RE，我下载下来数据本地评测可以过。。
在隔壁codevs上A了。。。
这题其实就是一个裸的最短路，只不过需要判定文化排斥问题。
所以只需要在求最短路的同时维护一下当前文化就好。
参考代码：
1 #include <iostream> 2 #include <cstring> 3 #include <cstdio> 4 #include <queue> 5 #define maxn 2333 6 #define INF 2147483647 7 using namespace std; 8 inline int read(){ 9 int num = 0; 10 char c; 11 while (( c=getchar()) == ' ' || c ==' ' || c == 'r'); 12 num = c - '0'; 13 while (isdigit(c = getchar())) 14 num = num * 10 + c - '0'; 15 return num; 16 } 17 struct Edge{ 18 int from,to,dis; 19 }; 20 struct node{ 21 int point; 22 int culture; 23 }; 24 Edge edge[maxn]; 25 int head[maxn]; 26 int dis[maxn]; 27 int tot = 0; 28 int n,k,m,s,t; 29 int u,v,d; 30 int refuse[maxn][maxn]; 31 int c[maxn]; 32 void add_edge(int from,int to, int dis){ 33 edge[++tot].from = head[from]; 34 edge[tot].to = to; 35 edge[tot].dis = dis; 36 head[from] = tot; 37 } 38 bool inq[maxn]; 39 void spfa(){ 40 memset(inq,false,sizeof(inq)); 41 for (int i=1;i<=n;i++) 42 dis[i] = INF; 43 dis[s] = 0; 44 queue<node> q; 45 node st; 46 st.point = s; 47 st.culture = c[s]; 48 q.push(st); 49 inq[st.point]= true; 50 while (!q.empty()){ 51 node u = q.front(); 52 q.pop(); 53 inq[u.point] = false; 54 for (int i = head[u.point];i;i = edge[i].from){ 55 int v = edge[i].to; 56 int w = edge[i].dis; 57 if (refuse[c[v]][u.culture]) 58 continue; 59 else{ 60 if (dis[u.point] + w < dis[v]){ 61 dis[v] = w + dis[u.point]; 62 if (!inq[v]){ 63 inq[v] = true; 64 node nextp; 65 nextp.culture = c[v]; 66 nextp.point = v; 67 q.push(nextp); 68 } 69 } 70 } 71 } 72 } 73 } 74 int main(){ 75 n = read();k = read();m = read();s = read();t = read(); 76 for (register int i=1;i<=n;i++) 77 c[i] = read(); 78 for (register int i=1;i<=k;i++) 79 for (register int j=1;j<=k;j++) 80 refuse[i][j] = read(); 81 for (register int i=1;i<=m;i++){ 82 u = read();v = read();d = read(); 83 add_edge(u,v,d); 84 add_edge(v,u,d); 85 } 86 spfa(); 87 if (dis[t] == INF) 88 printf("-1"); 89 else 90 printf("%d",dis[t]); 91 return 0; 92 }