苗火 Nicholas
[Data structures]Topological sort
2019-7-25 萧
#include <stdio.h>
#include <stdlib.h>

#define MAX 20
#define INFINIT 65535

typedef struct _ArcCell{
int adj; // Weight or flag about connection
int *info; // Other information
}ArcCell;

typedef char VertexType;

typedef enum{
DG,
DN,
UDG,
UDN
}GraphKind;

typedef struct _MGraph{
VertexType vexs[MAX];
ArcCell arcs[MAX][MAX];
int vexnum;
int arcnum;
GraphKind kind;
}MGraph;

int visited[MAX];

int LocateVex(MGraph *G, VertexType v)
{
int i=0;
while(i<G->vexnum && G->vexs[i] != v){
i++;
}
if(i<G->vexnum){
return i;
}else{
return -1;
}
}

int CreateUDG(MGraph *G)
{
int i,j,k;
char v1,v2;

scanf(" %d %d", &G->vexnum, &G->arcnum);
for(i=0; i<G->vexnum; i++){
scanf(" %c", &G->vexs[i] );
}
for(i=0; i<G->vexnum; i++){
for(j=0; j<G->vexnum; j++){
G->arcs[i][j].adj = INFINIT;
}
}
for(k=0; k<G->arcnum; k++){
scanf(" %c %c", &v1, &v2);
i=LocateVex(G, v1);
j=LocateVex(G, v2);
G->arcs[i][j].adj = 1;
}
return 1;
}

int FirstAdjvex(MGraph *G, int v)
{
int i=0;
while(i<G->vexnum && G->arcs[v][i].adj == INFINIT){
i++;
}
if(i<G->vexnum){
return i;
}else{
return -1;
}
}

int NextAdjvex(MGraph *G, int v, int w)
{
int i=w+1;
while(i<G->vexnum && G->arcs[v][i].adj == INFINIT){
i++;
}
if(i<G->vexnum){
return i;
}else{
return -1;
}

}

void FindInDegree(MGraph *G, int *indegree)
{
int i;
int j;
for(i=0; i<G->vexnum; i++){
indegree[i]=0;
for(j=0; j<G->vexnum; j++){
if(G->arcs[j][i].adj != INFINIT){
indegree[i]++;
}
}
}
}

int TopologicalSort(MGraph *G)
{
int indegree[MAX];
int stack[MAX];
int top = -1;
int w;
int i;
int count;

FindInDegree(G, indegree);
for(i=0; i<G->vexnum; i++){
if(!indegree[i]){
stack[++top] = i;
}
}

count = 0;

while(top>=0){
w = stack[top--];
printf(" %c->", G->vexs[w]);
++count;

for(i=0; i<G->vexnum; i++){
if(G->arcs[w][i].adj != INFINIT){
indegree[i]--;
if(indegree[i] == 0){
stack[++top] = i;
}
}
}

}

}

void main()
{
MGraph G;

printf("log.anycle.com\n\n");
printf("Create graph:\n");
CreateUDG(&G);
printf("\n");

printf("Topological sort:\n");
TopologicalSort(&G);
printf("\n");

}
发表评论:
昵称

邮件地址 (选填)

个人主页 (选填)

内容