Question: The Rhone river is both the main input and output of which lake?
About the article "Switzerland", section "Geography".

Candidate passages:
System identification techniques can utilize both input and output data (e.g.
eigensystem realization algorithm) or can only include the output data (e.g.
frequency domain decomposition).
Typically an input-output technique would be more accurate, but the input data is not always available. 
In economics, an input–output model is a quantitative economic technique that represents the interdependencies between different branches of a national economy or different regional economies.
Wassily Leontief (1905–1999) is credited with developing this type of analysis and took the Nobel Prize in Economics for his development of this model.
The International Input-Output Association is dedicated to advancing knowledge in the field of input–output study, which includes "improvements in basic data, theoretical insights and modelling, and applications, both traditional and novel, of input-output techniques."
Output parameters are often discouraged in modern programming, essentially as being awkward, confusing, and too low-level – commonplace return values are considerably easier to understand and work with.
Notably, output parameters involve functions with side effects (modifying the output parameter) and are semantically similar to references, which are more confusing than pure functions and values, and the distinction between output parameters and input/output parameters can be subtle.
Further, since in common programming styles most parameters are simply input parameters, output parameters and input/output parameters are unusual and hence susceptible to misunderstanding.
Output and input/output parameters prevent function composition, since the output is stored in variables, rather than in the value of an expression.
Thus one must initially declare a variable, and then each step of a chain of functions must be a separate statement.
For example, in C++ the following function composition:when written with output and input/output parameters instead becomes (for codice_46 it is an output parameter, for codice_48 an input/output parameter):In the special case of a function with a single output or input/output parameter and no return value, function composition is possible if the output or input/output parameter (or in C/C++, its address) is also returned by the function, in which case the above becomes: 
Rhodanien (French, the adjective derived from the river Rhone) may refer to:  the Rhone river or its valley  "le sillon rhodanien" (literally "the furrow of the Rhone"), which is the name of the long, straight Saône and Rhone river valleys, a deep cleft running due south to the Mediterranean and separating the Alps from the Massif Central  "Rhodanien", a dialect of the Lyon région, and of the Franco-Provençal language  "Provençal rhodanien", a dialect of the Nîmes, Arles and Avignon régions, and a sub-dialect of the Provençal dialect  "Le Rhodanien" (train), which ran between Geneva/Paris and Marseille  
In shells on Unix-like operating systems and in the modern Windows shell, filters default to getting their data from standard input (the main input stream) and writing their output to standard output (the main output stream); auxiliary input may come from command line flags or configuration files, while auxiliary output may go to standard error.
The command syntax for getting data from a device or file other than standard input is the input operator (codice_1).
Similarly, to send data to a device or file other than standard output is the output operator (codice_2).
To append data lines to an existing output file, one can use the append operator (codice_3).
Filters may be strung together into a pipeline with the pipe operator ("codice_4").
This operator signifies that the main output of the command to the left is passed as main input to the command on the right.