xycpplib

xycpplib lets a Python program compile and execute C++ source using the C++ compiler installed on the machine. It is useful for running competitive programming solutions, including GCC conveniences such as #include <bits/stdc++.h>, from Python.

It is not a source-to-source C++-to-Python translator: arbitrary C++ cannot be faithfully translated to Python. Instead, the original C++ is compiled, so programs work to the extent that the selected local compiler supports them.

Install

python -m pip install -e .

g++, clang++, or c++ must be available on PATH. Set XYCPPLIB_CXX to choose another compiler explicitly.

Use in a Python file

Python cannot contain bare C++ after an import: the Python parser rejects it before the import can run. Put the C++ in a string and call main to make the Python file behave like the C++ executable:

from xycpplib import main

main(r"""
#include <bits/stdc++.h>
using namespace std;
#define int long long
signed main(){
    int d,t; cin>>d>>t;
    int cnt=0;
    vector<int> a(d+1,0);
    vector<int> b(d+1,0);
    while(t--){
        int x,y; cin>>x>>y;
        a[x]--;
        if(a[x]<b[x]) b[x]=a[x];
        a[y]++;
    }
    for(int i:b) cnt+=(0-i);
    cout<<cnt;
}
""")

Run it normally and pipe input just as you would with a C++ binary:

Get-Content input.txt | python solution.py

For code that needs the output as a Python value, use run:

import xycpplib

answer = xycpplib.run(CPP_SOURCE, input="3 4\n1 2\n1 2\n2 3\n3 2\n")
assert answer == "2"

Executables are cached by source, compiler arguments, and selected compiler in the user's cache directory. Use xycpplib.clear_cache() to remove this library's cache.

Create a portable Python launcher

import xycpplib

xycpplib.write_python("solution.py", CPP_SOURCE)

The generated file embeds the C++ source and requires xycpplib plus a C++ compiler when it is run.