Description
On a single threaded CPU, we execute some functions. Each function has a unique id between 0 and N-1.
We store logs in timestamp order that describe when a function is entered or exited.
Each log is a string with this format: "{function_id}:{"start" | "end"}:{timestamp}". For example, "0:start:3" means the function with id 0 started at the beginning of timestamp 3. "1:end:2" means the function with id 1 ended at the end of timestamp 2.
A function's exclusive time is the number of units of time spent in this function. Note that this does not include any recursive calls to child functions.
The CPU is single threaded which means that only one function is being executed at a given time unit.
Return the exclusive time of each function, sorted by their function id.
Solution
1.Stack 更节省时间的做法
class Solution:
def exclusiveTime(self, n: int, logs: List[str]) -> List[int]:
stack = []
res=[0]*n
last_start = None
for log in logs:
nid,op,t = log.split(':')
nid,t=int(nid),int(t)
if op =="start":
if stack:
res[stack[-1]]+= t - last_start
stack.append(nid)
else:
t +=1
stack.pop()
interval = t - last_start
res[nid] += interval
last_start = t
return res
使用stack解决
class Solution:
def exclusiveTime(self, n: int, logs: List[str]) -> List[int]:
stack = []
res={}
for log in logs:
nid,op,t = log.split(':')
nid,t=int(nid),int(t)
if op =="start":
stack.append([nid,t])
else:
_,t_start = stack.pop()
t_start=int(t_start)
interval = t-t_start +1
if nid in res:
res[nid] += interval
else:
res[nid] = interval
if stack:
if stack[-1][0] not in res:
res[stack[-1][0]] =- interval
else:
res[stack[-1][0]] -= interval
return [res[k] for k in sorted(res.keys())]
