DFS Cormen

#include <bits/stdc++.h>
#define MAX 100000
using namespace std;
enum color {WHITE,GRAY,BLACK};
vector<vector<int>> adjList;
color vertex_color[MAX+1];
int parent[MAX+1];
int vertex_start[MAX+1];
int vertex_end[MAX+1];
int TIME = 0;
int n,m;
void addEdge(int u, int v)
{
    adjList[u].push_back(v);
}
void DFS_VISIT(int u)
{
    TIME = TIME+1;
    vertex_start[u] = TIME;
    vertex_color[u] = GRAY;
    cout << u << " ";
    for(int i = 0; i < adjList[u].size(); i++)
    {
        int v = adjList[u][i];
        if(vertex_color[v] == WHITE)
        {
            parent[v] = u;
            DFS_VISIT(v);
        }
    }
    vertex_color[u] = BLACK;
    TIME = TIME+1;
    vertex_end[u] = TIME;
}
void DFS()
{
    for(int i = 1; i <= n; i++)
    {
        vertex_color[i] = WHITE;
        parent[i] = 0;
    }
    TIME = 0;
    for(int i = 1; i <= n; i++)
    {
        if(vertex_color[i] == WHITE)
            DFS_VISIT(i);
        cout << endl;
    }
    //DFS_VISIT(2);
}
int main()
{
    freopen("a.txt","r",stdin);
    cin >> n >> m;
    adjList.resize(n+1);
    for(int i = 1; i <= m; i++)
    {
        int u,v;
        cin >> u >> v;
        addEdge(u,v);
    }
    DFS();
    return 0;
}