DFS Algorithm can't color acyclic graphs

Question

#include "pch.h"
#include <stdlib.h>
#include <stdio.h>
#include <time.h>
typedef struct node {
  int key;
  int color;
  int d;
  int f;
  struct node* parent;
  struct node* next;
} node;
typedef struct Graph {
  int nr;
  struct node** adj;
} Graph;

struct node* createNode(int v) {
    struct node* newNode = (node*)malloc(sizeof(struct node));
    newNode->key = v;
    newNode->next = NULL;
    return newNode;
}
    
struct Graph* createGraph(int n) {
    struct Graph* graph = (Graph*)malloc(sizeof(struct Graph));
    graph->nr = n;
    
    graph->adj = (node**)malloc((n+1) * sizeof(struct node*));
    
    int i;
    for (i = 0; i < n; i++)
        graph->adj[i] = NULL;
    
    return graph;
    
}
    
void addEdge(struct Graph* graph, int s, int d) {
    struct node* newNode = createNode(d);
    newNode->next = graph->adj[s];
    graph->adj[s] = newNode;
    
}
    
void printGraph(struct Graph* g) {
    for (int i = 0; i < g->nr; i++) {
        struct node* temp = g->adj[i];
        printf("\n%d -> ", i);
        while (temp) {
            printf("%d -> ", temp->key);
            temp = temp->next;
        }
        printf("\n");
    }   
}

// topological sort + disc. time + final time pt noduri 
void DFS_VISIT_test(Graph* G, node* u, int* time, node** s) {
    
    *time = *time + 1;
    u->d = *time;
    u->color = 1;
    
    node* v = G->adj[u->key];
    if (v) {
        while (v) {
            if (v->color == 0) {
                v->parent = u;
                DFS_VISIT_test(G, v, time,s);
            }
            v = v->next;
        }
    }
    //trebuia functie push dar am facut fara pt moment
    node* q = (node*)malloc(sizeof(node));
    q->next = (*s);
    q->key = u->key;
    (*s) = q;
    u->color = 2;
    *time = *time + 1;
    u->f = *time;
    
}
    
void DFStest(Graph* g) {
  node* s = (node*)malloc(sizeof(node));
  s->key = NULL;
  s->next = NULL;
  for (int i = 0; i < g->nr; i++) {
    g->adj[i]->color = 0;
    g->adj[i]->parent = NULL;
  }
  int time = 0;
  node* u;
  for (int i = 0; i < g->nr; i++) {
    u = g->adj[i];
    if (u->color == 0) {
      DFS_VISIT_test(g, u, &time,&s);
    }
  }
  //print stack
  while (s) {
    printf("%d", s->key);
    s = s->next;
  }
  printf("\n");
  //afisare discovery and final time
  for (int i = 0; i < g->nr; i++) printf("%d - %d %d\n", i, g->adj[i]-\>d, g->adj[i]->f);
}

int main(){
  Graph* g = createGraph(5);
  /*
   * pt topological sort, inca incerc
                             0
                           /   \
                          1     2
                          \      \
                           3     4
        
    */
    addEdge(g, 0, 2);
    addEdge(g, 0, 1);
    addEdge(g, 1, 3);
    addEdge(g, 2, 4);
    printGraph(g);
    DFStest(g);
    return 0;
}

Through trial and error I discovered the problem but I am dumbfounded to the solution, I am sorry if it may be an obvious one but I tried it for 6 hours and I cannot wrap my head around it. Let's say I dynamically allocate the missing g->adj[i], then the if(v) while(v) will have a problem because the nodes don't point to anything, how do I solve this?