c++实现图结构

目录

邻接矩阵构造图

1.1 图的深度优先搜索遍历实现

1.2 图的广度优先搜索遍历实现

1.3 最短路径算法

---

邻接矩阵构造图

class adjancyWDigraph {
private:
    //顶点数 n
    int n;
    //边数
    int e;
    //邻接矩阵
    int ** a;
    //当边不存在时，矩阵权值设置为noEdge;
    int noEdge;
public:
//设置一个迭代器，迭代与顶点v相邻的顶点
    class iterator {
    private:
        int * Row;
        int noEdge;
        int n;//共有多少个顶点
        int currentVertex;
​
    public:
        iterator(int* theRow, int thenoEdge, int numberOfVertics) {
            Row = theRow;
            noEdge = thenoEdge;
            n = numberOfVertics;
            currentVertex = 1;
        }
        int next() {
            for (int j = currentVertex; j <= n; j++) {
                if (Row[j] != noEdge) {
                    currentVertex = j + 1;
                    return j;
                }
            }
            currentVertex = n + 1;
            return 0;
        }
    };
    void bfs(int v, int reach[]);
    void dfs(int v, int reach[]);
​//生成一个指向顶点v迭代器的指针
    iterator * makeIterator(int theVertex) {
        return new iterator(a[theVertex], noEdge, n);
    }
};

1.1 图的深度优先搜索遍历实现

void  adjancyWDigraph::bfs(int v, int reach[]) {
    //创建一个队列
    queue q;
    //将头节点加入队列
    q.push(v);
    reach[v] = true;
    while (!q.empty()) {
        //取出q中的第一个结点,然后从队列中删除
        int w = q.front();
        q.pop();
        //初始化节点的迭代器，找到与他相连的节点
        iterator *iw = makeIterator(w);
        int u;
        //当节点的相邻节点存在时
        while ((u = iw->next()) != 0) {
            if (reach[u] == 0) {
                q.push(u);
                reach[u] = true;
            }
        }
        delete iw;
    }
}

1.2 图的广度优先搜索遍历实现

void adjancyWDigraph::dfs(int v, int reach[]) {
    reach[v] = true;
    iterator *iw = makeIterator(v);
    int u;
    while ((u = iw->next()) != 0&&reach[u]!=true) {
        dfs(u, reach);
    }
    delete iw;
}

1.3 最短路径算法

void adjancyWDigraph:: BFS_MIN_DISTANCE(int v, int reach[], int d[], int path[]) {
	//为了方便考虑，假设所有权值为1
	//d[]表示顶点v到i的最短距离，path表示是从哪个顶点过来的,初始化一下这两个数组
	for (int i = 1; i < n; i++) {
		d[i] = 100000;
		path[i] = -1;
		reach[i] = false;
	}
	d[v] = 0;
	reach[v] = true;
	queue q;
	q.push(v);
	while (!q.empty()) {
		int w = q.front();
		q.pop();
		iterator *iw = makeIterator(w);
		int u;
		//当节点的相邻节点存在时,遍历
		while ((u = iw->next()) != 0) {
			if (reach[u] == false) {
				d[u] = d[w] + 1;
				path[u] = w;
				q.push(u);
				reach[u] = true;
			}
		}
		delete iw;
	}
}