How to find time and space complexity of a program

An algorithm is basically steps that are required to solve a programming problem. Space complexity of an algorithm is basically amount memory that is required to run a specific algorithm. Space complexity is basically sum of:. To calculate space complexity of an algorithm you have to assign 1 unit of space to operations where it requires a memory.

For example: creating a new variable require some space let say it is 1 unit of space. We are not going to learn in depth about how to exactly calculate space required by a program rather we would learn about how many unit of space does a program require to solve a specfic problem. In above example, we have fixed part and moving part.

Save Article. Like Article. Python3 program for the above approach. Function to find a pair in the given. Iterate through all the pairs. Check if the sum of the pair. This code is contributed by splevel WriteLine "True" ;. WriteLine "False" ;. This code is contributed by subhamsingh Python program for the above approach.

Function to count frequencies of array items. Traverse through array elements and. Traverse through map and prfrequencies. This code is contributed by Shubham Singh. Next Mimic the Linux adduser command in C. Recommended Articles.

Article Contributed By :. Easy Normal Medium Hard Expert. NOTE : We are interested in rate of growth of time with respect to the inputs taken during the program execution.

We can prove this by using time command. And compile that code on Linux based operating system Fedora or Ubuntu with below command: gcc program. Also, you will get different timings on the different machine. Even you will not get the same timings on the same machine for the same code, the reason behind that the current network load.

Now, the question arises if time complexity is not the actual time require executing the code then what is it? The answer is : Instead of measuring actual time required in executing each statement in the code, we consider how many times each statement execute. For example:. So, time complexity is constant: O 1 i. Hello Word!!!

So, time complexity of above code is O N. Skip to content. Change Language.