Question

这是我的代码，它使用邻接列表实现图形并执行广度优先搜索（BFS）和深度优先搜索（DFS）。在创建图形和添加边缘时，我遇到了创建图形时出现故障的问题。我不确定我用过的指针。你能说出我错在哪里吗？

#include "Graph.h"
#include <iostream>
using namespace std;

int Graph::pop()
{
    if (top = -1) {
        cout << "empty";
        return 0;
    } else
        return stack[top--];
}

void Graph::push(int value)
{
    if (top >= 50) {
        cout << "full";

    } else
        stack[++top] = value;
}

void Graph::add(int val)
{
    if (rear != 49)
        qu[++rear] = val;
    else
        cout << "full";
}

int Graph::del()
{
    if (rear == front) {
        cout << "empty";
        return 0;
    } else
        front += 1;
    return qu[front];
}

int Graph::gethead()
{
    return rear;
}

int Graph::gettail()
{
    return front;
}

node *Graph::createnode(int t)
{
    node *temp;
    temp = new node;
    temp->val = t;
    temp->next = NULL;
    return temp;
}



Graph::Graph()
{
    rear = -1;
    front = -1;
    top = -1;
}

Graph::Graph(int t)
{
    struct arr r[t];
    a = r;
    for (int i = 0; i < t; i++) {
        a[i].key = i;
        a[i].begin = NULL;
        a[i].end = NULL;
    }

    int q[t];
    p = q;
    for (int k = 0; k < t; k++) {
        p[k] = 0;
    }
}

void Graph::visited(int v1)
{
    p[v1] = 1;
}

bool Graph::isvisited(int v1)
{
    if (p[v1] == 1)
        return true;
    else
        false;
}

void Graph::addEdge(int v1, int v2)
{

    if (a[v1].begin == NULL) {
        node *temp = createnode(v2);
        a[v1].begin = temp;
        a[v1].end = temp;
    } else {
        node *temp = createnode(v2);
        node *temp1 = a[v1].end;
        temp1->next = temp;
        a[v1].end = temp;
    }

    if (a[v2].begin == NULL) {
        node *temp = createnode(v1);
        a[v2].begin = temp;
        a[v2].end = temp;
    } else {
        node *temp = createnode(v1);

        //node *temp2=a[v2].end;
        //temp2->next=temp;
        a[v2].end->next = temp;
        //a[v2].end->next=temp;
        a[v2].end = temp;
    }
}

void Graph::deleteEdge(int v1, int v2)
{
    node *temp;
    temp = a[v1].begin;
    if (a[v1].begin->val == v2) {
        a[v1].begin = a[v1].begin->next;
        delete(temp);
        temp = NULL;
    } else {
        node *t = temp->next;
        while (t != NULL) {
            if (t->val == v2) {
                temp->next = t->next;
                delete(t);
            } else {
                temp = t;
                t = t->next;
            }
        }
    }


    node *temp1;
    temp1 = a[v2].begin;
    if (a[v2].begin->val == v1) {
        a[v2].begin = a[v2].begin->next;
        delete(temp);
        temp = NULL;
    } else {
        node *t = temp->next;
        while (t != NULL) {
            if (t->val == v1) {
                temp->next = t->next;
                delete(t);
            } else {
                temp = t;
                t = t->next;
            }
        }
    }
}

void Graph::BFS(int source)
{
    add(source);
    visited(source);
    node *temp = a[source].begin;
    while (temp != a[source].end) {
        add(temp->val);
    }
    int r = del();
    cout << r << endl;
    while (gethead() != gettail()) {
        int v1 = del();
        visited(v1);
        node *temp1;
        temp1 = a[v1].begin;
        while (temp1 != NULL) {
            if (p[temp1->val] != 1) {
                add(temp1->val);
                temp1 = temp1->next;
            } else
                temp1 = temp1->next;
        }
        if (temp1 == NULL)
            cout << v1 << endl;
    }
}

void Graph::DFS(int source)
{
    int c = source;
    cout << c;
    visited(c);
    node *temp2 = a[source].begin;
    while (a[source].end != NULL) {
        push(temp2->val);
        temp2 = temp2->next;
    }
    c = pop();
    while (top != -1) {
        node *temp = a[c].begin;
        if (p[c] != 1) {
            cout << c;
            while (temp != NULL) {
                push(temp->val);
                temp = temp->next;
                visited(c);
                c = pop();
            }
        }
        if (p[c] = 1) {
            c = pop();
        }
    }
}

Answer 1

第一个明显的错误是，在if (top = -1)行中，=应替换为==。

用于创建图形和广度优先搜索（BFS）和深度优先搜索（DFS）的邻接列表

1 个答案: