一步一步写算法(之prim算法 中) (二)

2014-11-23 23:55:15 · 作者: · 浏览: 50
VECTEX* pVectex;

LINE* pLine;

int index;

int start;

pHead = NULL;

for(index = 0; index < pMiniTree->node_num; index++){

start = pMiniTree->pNode[index];

pVectex = find_vectex_in_graph(pGraph->head, start);

pLine = pVectex->neighbor;

while(pLine){

insert_line_into_queue(&pHead, start, pLine->end, pLine->weight);

pLine = pLine->next;

}

}

if(NULL == pHead)

return;

delete_unvalid_line_from_list(&pHead, pMiniTree);

if(NULL == pHead)

return;

sort_for_line_list(&pHead);

memmove(pDirLine, pHead, sizeof(DIR_LINE));

while(pHead){

prev = pHead;

pHead = pHead->next;

free(prev);

}

return;

}

e)添加节点函数,将尚不是最小生成树的点纳入到最小生成树当中去

void insert_node_into_mini_tree(DIR_LINE* pLine, MINI_GENERATE_TREE* pMiniTree)

{

int index;

for(index = 0; index < pMiniTree->node_num; index ++){

if(pLine->start == pMiniTree->pNode[index]){

pMiniTree->pNode[pMiniTree->node_num++] = pLine->end;

return;

}

}

pMiniTree->pNode[pMiniTree->node_num++] = pLine->start;

return;

}

void insert_node_into_mini_tree(DIR_LINE* pLine, MINI_GENERATE_TREE* pMiniTree)

{

int index;

for(index = 0; index < pMiniTree->node_num; index ++){

if(pLine->start == pMiniTree->pNode[index]){

pMiniTree->pNode[pMiniTree->node_num++] = pLine->end;

return;

}

}

pMiniTree->pNode[pMiniTree->node_num++] = pLine->start;

return;

}

注意事项:

(1)d、e是c中调用的子函数,如果大家观察一下就明白了

(2)最小生成树是按照自顶向下的顺序编写的,虽然c中的子函数完成了,但是d中还有两个子函数没有着落

(3)d中的函数delete_unvalid_line_from_list、sort_for_line_list会在下一篇中继续介绍

(4)算法只要能够按照手工计算的流程编写出来,基本上问题不大,但是一些细节还是要小心注意的

【待续】