阿泰的邻居有几个

运行下面这段程序：

NAMES = ["阿岚", "小满", "阿泰", "南风", "北辰"]
EDGES = [("阿岚", "小满"), ("阿岚", "阿泰"),
         ("小满", "阿泰"), ("阿泰", "南风")]

def build_adj():
    adj = {}
    for n in NAMES:
        adj[n] = []
    for a, b in EDGES:
        adj[a].append(b)
        adj[b].append(a)
    return adj

print(len(build_adj()["阿泰"]))