链式前向星DFS

采用链式前向星存图的DFS:

#include <iostream>
#include <cmath>
#include <cstdio>
#include <cstring>
#include <cstdlib>
#include <algorithm>
#include <queue>
using namespace std;
typedef long long LL;

const int maxN = 100 + 3;
const int maxM = 1000 + 3;
int head[maxN];
int visited[maxN];
int N, M;

struct EdgeNode
{
    int to;
    int w;
    int next;
};
EdgeNode Edges[maxM];

void DFS(int x)
{
    visited[x] = 1; //标记当前节点已被访问
    for(int i = head[x]; i != -1; i = Edges[i].next)
    {
    //对于每个未被访问的相邻节点，调用DFS，遍历结束后、尝试其他支路
        if( !visited[Edges[i].to] )
            DFS(Edges[i].to);
    }
}

int main()
{
    freopen("input.txt", "r", stdin);
    memset(head, -1, sizeof(head));
    cin >> N >> M;
    for(int i = 1; i <= M; i++)
    {
        int x, y ,z;
        cin >> x >> y >> z;
        Edges[i].to = y;
        Edges[i].w = z;
        Edges[i].next = head[x];
        head[x] = i;
    }
    memset(visited, 0, sizeof(visited));
    DFS(1);
    return 0;
}