Auto input in VS code terminal from input.txt whenever compiled

Question

Generally we need to type the input after running any file where we have std::cin, like the c++ code in below

    int M,N;
    cin>>M>>N;
    int i,a[M],b[N];
    for(i=0;i<M;i++)
    {
        cin>>a[i];
    }
    for(i=0;i<N;i++)
    {
        cin>>b[i];
    }
    Solution ob;
    cout<<ob.countPairs(a, b, M, N)<<endl;

I just don't like to enter the same big input every time. So I want to automate this process for the same input, say I save my input in a file called input.txt and after running the file, it should take the input from input.txt and output the results. Ofc saving input to the clipboard is one way but I might want to copy other things while coding and copy-pasting is itself is again one small job.

I use VS code editor in ubuntu and run code in terminal using coderunner extension.

Answer 1

Scripting

Write your long input into a file, input.txt:

the quick brown fox jumped over the lazy dog

Use a bash script, script.sh:

# Compile your program, ie:
clang++ source.cpp -o application

# Check compilation succeeded
if [[ $? -ne 0 ]]; then
    echo "compilation failed"
    exit 1
fi

# Pipe your input into the application
cat input.txt | ./application 

Finally, invoke your script:

$ bash script.sh

To Read:

• Piping input to applications
• Return values in bash