poj 2367 Genealogical tree

裸的拓扑排序 图用邻接表表示

 

方法是dfs

 

#include<stdio.h>#include<string.h>const int MAXN = 1000;struct edge{int u, v, next;}e[MAXN];int n;int first[MAXN], cnt;bool visit[MAXN], f;int sort[MAXN], top;void dfs(int s){if(visit[s])return;visit[s] = true;for(int x = first[s]; x != -1; x = e[x].next){if(!visit[e[x].v])dfs(e[x].v);}sort[++top] = s;}void toposort(){memset(visit, false, sizeof(visit));top = -1;for(int i = 1; i <= n; ++i){if(!visit[i])dfs(i);}}int main(){ scanf("%d",&n); memset(first, -1, sizeof(first));for(int i = 1, cnt = 0; i <= n; ++i){int a;while(true){scanf("%d",&a);if(!a) break;e[cnt].u = i;e[cnt].v = a;e[cnt].next = first[i];first[i] = cnt;cnt++;}}toposort();bool f = true;while(top != -1){if(f)f = false;elseprintf(" ");printf("%d",sort[top--]);}printf("/n");return 0;}