Topological sort using DFS in C++ code example

Example 1: insertion sort in python

def tri_insert(tab): 
for i in range(1, len(tab)): 
        k = tab[i] 
        j = i-1
        while j >= 0 and k < tab[j] : 
                tab[j + 1] = tab[j] 
                j -= 1
        tab[j + 1] = k


    return tab

Example 2: topological sort cp algorithms

int n; // number of vertices
vector<vector<int>> adj; // adjacency list of graph
vector<bool> visited;
vector<int> ans;

void dfs(int v) {
    visited[v] = true;
    for (int u : adj[v]) {
        if (!visited[u])
            dfs(u);
    }
    ans.push_back(v);
}

void topological_sort() {
    visited.assign(n, false);
    ans.clear();
    for (int i = 0; i < n; ++i) {
        if (!visited[i])
            dfs(i);
    }
    reverse(ans.begin(), ans.end());
}