def pure_dijkstra(nodes, adj, start, end):
    dist = [float('inf')] * nodes
    dist[start] = 0
    visited = [False] * nodes

    cur = start
    
    while True:
        if cur == -1:
            break

        if cur == end:
            break

        for next, d in adj[cur]:
            if not visited[next]:
                new = dist[cur] + d
                if new < dist[next]:
                    dist[next] = new
        
        visited[cur] = True
        
        # Finding min node
        min_node = -1
        min_val = float('inf')
        for n in range(nodes):
            if not visited[n] and dist[n] < min_val:
                min_node = n
                min_val = dist[n]
        cur = min_node
    
    return dist[end]