拓扑排序

感觉总是无视拓扑排序也不太好，就来了2道模板题。。不造哪个时候又给忘了。。

codevs 1833

 1 #include<bits/stdc++.h>
 2 #define inc(i,l,r) for(int i=l;i<=r;i++)
 3 #define dec(i,l,r) for(int i=l;i>=r;i--)
 4 #define link(x) for(edge *j=h[x];j;j=j->next)
 5 #define mem(a) memset(a,0,sizeof(a))
 6 #define inf 1e9
 7 #define ll long long
 8 #define succ(x) (1<<x)
 9 #define NM 10000+5
10 #define nm 25000+5
11 using namespace std;
12 int read(){
13     int x=0,f=1;char ch=getchar();
14     while(!isdigit(ch)){if(ch=='-')f=-1;ch=getchar();}
15     while(isdigit(ch))x=x*10+ch-'0',ch=getchar();
16     return x*f;
17 }
18 struct edge{
19     int t;
20     edge *next;
21 }e[nm],*h[NM],*o=e;
22 void add(int x,int y){
23     o++;o->t=y;o->next=h[x];h[x]=o;
24 }
25 int n,m,v[NM],s,_x,_y;
26 queue<int >q;
27 void bfs(){
28     inc(i,1,n)if(!v[i])q.push(i);
29     while(!q.empty()){
30         int t=q.front();q.pop();
31         link(t)if(v[j->t]){
32             v[j->t]--;
33             if(!v[j->t])q.push(j->t);
34         }
35     }
36 }
37 int main(){
38     n=read();m=read();
39     inc(i,1,m){
40         _x=read();_y=read();
41         add(_x,_y);v[_y]++;
42     }
43     bfs();
44     inc(i,1,n)if(v[i])s++;
45     if(!s)puts("o(∩_∩)o");
46     else printf("T_T\n%d\n",s);
47     return 0;
48 }

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hdu 1285 顺便学了优先队列

 1 //#include<bits/stdc++.h>
 2 #include<cstdio>
 3 #include<algorithm>
 4 #include<iostream>
 5 #include<cstring>
 6 #include<queue>
 7 #define inc(i,l,r) for(int i=l;i<=r;i++)
 8 #define dec(i,l,r) for(int i=l;i>=r;i--)
 9 #define link(x) for(edge *j=h[x];j;j=j->next)
10 #define mem(a) memset(a,0,sizeof(a))
11 #define inf 1e9
12 #define ll long long
13 #define succ(x) (1<<x)
14 #define NM 500+5
15 using namespace std;
16 int read(){
17     int x=0,f=1;char ch=getchar();
18     while(!isdigit(ch)){if(ch=='-')f=-1;ch=getchar();}
19     while(isdigit(ch))x=x*10+ch-'0',ch=getchar();
20     return x*f;
21 }
22 struct edge{
23     int t;
24     edge *next;
25 }e[NM*NM],*h[NM],*o;
26 int n,m,v[NM],_x,_y,f;
27 struct cmp{
28     bool operator ()(int &a,int &b){
29         return a>b;
30     }
31 };
32 priority_queue<int,vector<int>,cmp>q;
33 void add(int x,int y){
34     o++;o->t=y;o->next=h[x];h[x]=o;
35 }
36 void bfs(){
37     inc(i,1,n)if(!v[i])q.push(i);
38     while(!q.empty()){
39         int t=q.top();q.pop();v[t]--;
40         if(f)putchar(' ');
41         printf("%d",t);f++;
42         link(t){
43             v[j->t]--;
44             if(v[j->t]==0)q.push(j->t);
45         }
46     }
47 }
48 int main(){
49 //    freopen("data.in","r",stdin);
50 //    freopen("test.out","w",stdout);
51     while(scanf("%d%d",&n,&m)!=EOF){
52         mem(v);mem(h);o=e;f=0;
53     inc(i,1,m){
54         _x=read();_y=read();
55         add(_x,_y);v[_y]++;
56     }
57     bfs();
58     printf("\n");
59     }
60     return 0;
61 }

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 15noip D1T2貌似也可以拓扑？