KosaRaju strongly connected components

#include <bits/stdc++.h>

#define MAX_N 20001
#define ll long long int
using namespace std;
int n, m;

struct Node {
  vector < int > adj;
  vector < int > rev_adj;
};

Node g[MAX_N];

stack < int > S;
bool visited[MAX_N];

int component[MAX_N];
vector < int > components[MAX_N];
int numComponents;

void dfs_1(int x) {
  visited[x] = true;
  for (int i = 0; i < g[x].adj.size(); i++) {
    if (!visited[g[x].adj[i]]) dfs_1(g[x].adj[i]);
  }
  S.push(x);
}

void dfs_2(int x) {
  printf("%d ", x);
  component[x] = numComponents;
  components[numComponents].push_back(x);
  visited[x] = true;
  for (int i = 0; i < g[x].rev_adj.size(); i++) {
    if (!visited[g[x].rev_adj[i]]) dfs_2(g[x].rev_adj[i]);
  }
}

void Kosaraju() {
  for (int i = 0; i < n; i++)
    if (!visited[i]) dfs_1(i);

  for (int i = 0; i < n; i++)
    visited[i] = false;

  while (!S.empty()) {
    int v = S.top();
    S.pop();
    if (!visited[v]) {
      printf("Component %d: ", numComponents);
      dfs_2(v);
      numComponents++;
      printf("\n");
    }
  }
}

int main() {

  cin >> n >> m;
  int a, b;
  while (m--) {
    cin >> a >> b;
    g[a].adj.push_back(b);
    g[b].rev_adj.push_back(a);
  }

  Kosaraju();
  printf("Total number of components: %d\n", numComponents);

  return 0;
}