DIY: Exclusive Time of Functions

Solve the interview question "Exclusive Time of Functions" in this lesson.

Problem statement

You are given a list logs, where logs[i] represents the ithith log message formatted as a string, {function_id}:{"start" | "end"}:{timestamp}. For example, 0:start:3 means a function call with a function of ID 0 starts at the beginning of timestamp 3, and 1:end:2 means a function call with a function of ID 1 ends at the end of timestamp 2.

Note: A function can be called multiple times, possibly recursively.

A function’s exclusive time is the sum of the execution times for all of the calls to that function anywhere in the program. For example, if a function is called twice, one call executes for 2 time units and the other executes for 1 time unit, the exclusive time is 2+1=32+1=3.


The input will be a variable with the total number of functions and a list of strings with each string containing information about a specific function. The following is an example input:

n = 2, logs = ["0:start:0", "1:start:3", "1:end:6", "0:end:10"]


The output will be a list of the exclusive time of each function. The following is an example output of the above input:

[7, 4]

In this example, the function with id 0 has an exclusive time of 7 stored at index 0, and the function with id 1 has an exclusive time of 4 stored at index 1.

Coding exercise

Implement the exclusive_time(n, logs) function, where n is the number of functions and logs is the list containing the formatted string of function information. The function returns an array with the exclusive time of the functions at their respective indices of the function IDs.

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