Topology Sort Template

Topological ordering is the linear ordering of the ADG (a direction-free graph)

Template:

Queue implementation

#include <cstdio>#include<cstring>#include<algorithm>#include<queue>using namespacestd;intindegree[ -];queue<int>Q;intn,m;BOOLmap[ -][ -];inta[ -];intTopointN) {    intCNT =1;  while(!q.empty ()) Q.pop ();  for(inti =1; I <= N; i++)        if(Indegree[i] = =0) Q.push (i); intu;  while(!Q.empty ()) {u=Q.front (); A[cnt++] =u;        Q.pop ();  for(inti =1; I <= N; i++){            if(Map[u][i]) {Indegree[i]--; if(Indegree[i] = =0) Q.push (i); }        }        if(CNT = =N) {             for(inti =1; I <= N; i++) printf ("%d", A[i]); }        Elseprintf"The network has a cycle"); }}intMain () {intu,v;  while(~SCANF ("%d%d",&n,&m)) {memset (Indegree,0,sizeof(Indegree)); memset (Map,0,sizeof(map));  for(inti =0; I < m; i++) {scanf ("%d%d",&u,&v); if(!Map[u][v]) Indegree[v]++; MAP[U][V]=1;    } topo (n); }    return 0;}

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adjacency Table Implementation

#include <cstdio>#include<cstring>#include<algorithm>#include<queue>using namespacestd;Const intM =100005;structedge{intv,nxt; Edge () {} Edge (intVintNXT): V (v), NXT (NXT) {}}e[m];inthead[m],e;intA[m];intIndegree[m];intn,m,u,v;voidAddedge () {e[e]=Edge (V, Head[u]); Head[u]= e++;}voidInti () {E=0; memset (Head,-1,sizeof(head)); Memset (A,0,sizeof(a)); memset (Indegree,0,sizeof(Indegree));}voidTopointN) {Queue<int>Q; intCNT =1;  while(!q.empty ()) Q.pop ();  for(inti =1; I <= N; i++)        if(Indegree[i] = =0) Q.push (i);  while(!Q.empty ()) {        intU =Q.front (); A[cnt++] =u;        Q.pop ();  for(inti = Head[u]; ~u; i =e[i].nxt) {INDEGREE[E[I].V]--; if(INDEGREE[E[I].V] = =0) Q.push (E[I].V); }    }}intMain () { while(~SCANF ("%d%d",&n,&m)) {         for(inti =1; I <= m; i++) {scanf ("%d%d",&u,&v); INDEGREE[V]++;        Addedge ();    } topo (n); }    return 0;} 

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Topology Sort Template