diff --git a/problems/0454.四数相加II.md b/problems/0454.四数相加II.md index 7bb24e59..4e61dc2f 100644 --- a/problems/0454.四数相加II.md +++ b/problems/0454.四数相加II.md @@ -161,15 +161,9 @@ class Solution(object): # count=0 # for x3 in nums3: # for x4 in nums4: -# key = -x3-x4 -# value = hashmap.get(key) - - # dict的get方法会返回None(key不存在)或者key对应的value - # 所以如果value==0,就会继续执行or,count+0,否则就会直接加value - # 这样就不用去写if判断了 - -# count += value or 0 - +# key = 0 - x3 - x4 +# value = hashmap[key] # 若差值(key)不存在,则value被赋值0 +# count += value # return count ```