This is my code:

```
node2vec = {}
f = open('embed_hep.txt', 'rb')
for i, j in enumerate(f):  # i:index j:item
    if j != '\n':
        node2vec[i] = map(float, j.strip().decode("utf-8").split(' '))
f1 = open('test_graph.txt', 'rb')
edges = [map(int, i.strip().decode("utf-8").split('\t')) for i in f1]
nodes = list(set([i for j in edges for i in j]))
a = 0
b = 0
for i, j in edges:
    if i in node2vec.keys() and j in node2vec.keys():
        dot1 = np.dot(node2vec[i], node2vec[j])
        random_node = random.sample(nodes, 1)[0]
        while random_node == j or random_node not in node2vec.keys():
            random_node = random.sample(nodes, 1)[0]
        dot2 = np.dot(node2vec[i], node2vec[random_node])
        if dot1 > dot2:
            a += 1
        elif dot1 == dot2:
            a += 0.5
        b += 1

print(float(a) / b)

```

this is error:
line 14, in 

```
for i, j in edges:

```

ValueError: not enough values to unpack (expected 2, got 0)

embed\_hep.txt:

```
1 3 6 8
3 5 7 0
3 6 8 9

```

text\_graph.txt:

```
1698    2012
779     778
804     815

```