Problem summary

Implement a command line utility, that can be invoked in common Linux operating systems, which accepts tabular (single-column) input via standard input and writes tabular (single-column) output. Lines of input and output will consist of only numerical values, and the program will transform the input values into output values according to some rules.

The utility will be named compute or compute.py and will be able to be assume some limited things about the environment where it will be run. Two packaging options are available for submitting a valid solution.

Input

Input will consist of up to 100 lines of numbers - all decimal numbers between 0.0 and 1,000,000,000.0 (inclusive). The compute executable or compute.py script must also accept two numerical arguments provided on the command line.

The first argument will be referred as a threshold value. It will be a number between 0.0 and 1,000,000,000.0 (inclusive).

The second argument will be referred to as the limit value. It will also be between 0.0 and 1,000,000,000.0 (inclusive).

How to produce output from this input is described below.

Output

The program must only output numbers. Every line of output must contain one (and only one) numerical value. Do not output anything other than what is required. One number will be written for every number accepted via standard input. One extra number will be written at the very end, as explained below.

Since there are up to 100 lines of input (0 <= n <= 100), there will therefore be n+1 lines of output expected from a valid solution. The last line of output (line n+1) will be a value that represents the cumulative sum of all the values previously written. The preceding output values will depend on the arguments, which will be used to transform the input into the output.

Example

Command line:

# compute threshold limit
compute 1000 20000000

Standard input:

19.0
0.0
1000
1001.5
20000
25000000.0

Standard output:

0.0
0.0
0.0
1.5
19000.0
19980998.5
20000000.0

Explanation

Given the n inputs, outputs 1..n will be produced based on these values, taking into account the threshold and limit arguments.

The threshold argument will be used to modify every input so that if the input amount is greater than the threshold, the output amount will be the portion of the input value that exceeds the threshold. If the input is less than the threshold, the output should be zero. Put another way, the output value will be the larger of 0.0 or the value of [input] - [threshold].

The limit amount serves to further constrain the output values. The cumulative sum of of all n outputs must never exceed this value, however the individual output values must be maximized in the order they are given without breaking the rules imposed by threshold and limit.

After all inputs are processed, output value n+1 will be written. It must be equal to the sum of all n output values. It follows from the rules above that output n+1 must always be less than or equal to the limit argument specified.

Additional examples

Threshold

The threshold argument works to modify each input value as explained above. This table demonstrates handling of individual inputs given specific threshold values, but is not a complete example.

input	threshold	output
0.0	0.0	0.0
10.0	0.0	10.0
0.0	10.0	0.0
5.0	10.0	0.0
10.0	5.0	5.0
20.0	5.0	15.0

Limit

The limit argument works to modify inputs on an aggregate basis. The easiest way to illustrate this is to assume a threshold of 0.0 and demonstrate the effect. This is a complete example which includes the n+1 "sum" output.

threshold == 0.0; limit == 100.0

input	output
0.0	0.0
10.0	10.0
50.0	50.0
50.0	40.0
10.0	0.0
20.0	0.0
	100.0

Note: The cumulative sum of the first four inputs after applying the threshold has exceeded the limit, thus the fourth output is 40.0 to ensure maximum output values while respecting the limit argument.

threshold == 0.0; limit == 0.0

input	output
0.0	0.0
10.0	0.0
20.0	0.0
	0.0

Important considerations worth noting/repeating

• Input lines will consist of decimal or integer numbers (i.e. The input numbers will be separated by newline characters).
• The output should consist of n+1 lines, each containing one number.
• Decimal precision must be accurate to the tenths place. Inputs will not have precision beyond the tenths place, so rounding should be unnecessary. If any rules around input/output precision are ambiguous, feel free to state your assumptions in code comments.

Submission guidelines

You must provide a solution that contains one of the following files:

1. compile
2. compute
3. compute.py
4. Dockerfile

Supported languages

If you provide compile, we'll assume a C++ solution and use it to build your compute executable before calling it. compile can invoke make or g++. You can assume that make is available in version 4.x or higher. g++ will be available as gcc version 9.x or higher.

If you provide compute, we'll assume your solution is a python script using the unix shebang as in:

#!/usr/bin/env python

If you provide neither of the above files, but you do provide compute.py, we'll call your program with the python interpreter.

You can assume that executing python --version will emit Python 3.6.9 or newer.

As a fourth and final option, you may provide none of the first three files. Instead, we'll use the Dockerfile provided to build and execute your program. This allows you to use some other language or set of tools.

Packaging

You can provide your solution as a git repository URL that can be cloned, or as a zip file that contains the appropriate files. If you submit a git repository URL, it must be publicly available so we can clone it. If submitting a zip file, it must be named solution.zip.

Do not submit a solution containing a compiled binary program.

Expected operation

The following steps should lead to successful execution of your program, depending on which type of submission you choose:

Initial steps

git

1. git clone <URL> projectfolder
2. cd projectfolder

zip

1. unzip -d projectfolder solution.zip
2. cd projectfolder

Execution steps

docker

1. docker build -t solution .
2. cat input | docker run -i --rm solution:latest compute 100 5000

non-docker

1. ./compile # optional step when compile file present
2. cat input | ./compute 100 500 # when compute file present
3. cat input | python ./compute.py 100 500 # when compute.py file present

Note that the arguments provided may not be 100 and 500!