• May 1, 2025
• in Fun
• 3 min read

Run Codeforces 1952J codes 20000x faster

I have created a Codeforces 1952J language to C++ transpiler, the resulting compiled code is 20000x* faster compared to the reference implementation.

Code

#include <bits/stdc++.h>
using namespace std;
#define int long long
#ifndef yoshi_likes_e4
#define endl '\n'
#endif
#define problem ""
#define multitest 0
#define debug(x) cerr << #x << " = " << x << endl;
void init()
{
}
map<string, bool> var_type;
void Add_variable(string k)
{
    bool ok = 0;
    try
    {
        std::stoi(k);
        ok = true;
    }
    catch (const std::invalid_argument &e)
    {
    }
    catch (const std::out_of_range &e)
    {
    }
    if (!ok)
    {
        int pos = k.find('[');
        if (pos == string::npos)
            var_type[k] = 0;
        else
            var_type[string(k.begin(), k.begin() + pos)] = 1;
    }
}
void Yoshi()
{
    vector<vector<string>> code;
    string s;
    while (getline(cin, s))
    {
        stringstream t(s);
        code.push_back({});
        string x;
        while (t >> x)
            code.back().push_back(x);
    }
    map<int, int> label_id;
    int lid = 0;
    for (auto &lines : code)
    {
        if (lines[0] == "simp")
        {
            int v = stoi(lines[2]) - 1;
            if (label_id.find(v) == label_id.end())
                label_id[v] = lid++;
        }
        if (lines[0] == "vibe")
            Add_variable(lines[2]), Add_variable(lines[4]);
        if (lines[0] == "bruh")
            Add_variable(lines[1]), Add_variable(lines[5]);
        if (lines[0] == "*slaps")
            Add_variable(lines[1]), Add_variable(lines[5].substr(0, lines[5].size() - 1));
        if (lines[0] == "rip")
            Add_variable(lines[2]), Add_variable(lines[6]);
        if (lines[0] == "yoink")
            Add_variable(lines[1]);
        if (lines[0] == "yeet")
            Add_variable(lines[1]);
    }
    vector<string> var0, var1;
    for (auto &[u, v] : var_type)
        if (v)
            var1.push_back(u);
        else
            var0.push_back(u);
    cout << R""""(#include <bits/stdc++.h>
using namespace std;
void input(int &x)
{
    string s;
    getline(cin, s);
    x = stoi(s);
}
void input(vector<int> &x)
{
    string s;
    getline(cin, s);
    stringstream t(s);
    while (t >> s)
        x.push_back(stoi(s));
})"""";
    cout << "\nint main(){\ncin.tie(0)->sync_with_stdio(0);\n";
    if (var0.size())
    {
        cout << "int ";
        for (auto &i : var0)
            cout << i << (&i != &var0.back() ? ", " : ";\n");
    }
    if (var1.size())
    {
        cout << "vector<int> ";
        for (auto &i : var1)
            cout << i << (&i != &var1.back() ? ", " : ";\n");
    }
    for (auto &lines : code)
    {
        if (label_id.find(&lines - &code[0]) != label_id.end())
            cout << "L" << label_id[&lines - &code[0]] << ":\n";
        if (lines[0] == "simp")
            cout << "goto L" << label_id[stoi(lines[2]) - 1] << ";\n";
        if (lines[0] == "vibe")
            cout << "if (" << lines[2] << " > " << lines[4] << ')' << "\n";
        if (lines[0] == "bruh")
            cout << lines[1] << " = " << lines[5] << ";\n";
        if (lines[0] == "*slaps")
            cout << lines[5].substr(0, lines[5].size() - 1) << " += " << lines[1] << ";\n";
        if (lines[0] == "rip")
            cout << lines[2] << " -= " << lines[6] << ";\n";
        if (lines[0] == "yoink")
            cout << "input(" << lines[1] << ");\n";
        if (lines[0] == "yeet")
            cout << "cout << " << lines[1] << " << \"\\n\";\n";
        if (lines[0] == "go")
            cout << "return 0;\n";
    }
    cout << "}" << endl;
}
signed main()
{
#ifndef yoshi_likes_e4
    ios::sync_with_stdio(0);
    cin.tie(0);
    if (fopen(problem ".inp", "r"))
    {
        freopen(problem ".inp", "r", stdin);
        freopen(problem ".out", "w", stdout);
    }
#endif
    init();
    int t = 1;
#if multitest
    cin >> t;
#endif
    while (t--)
        Yoshi();
}

*: Selection sort performance:

\(n=3000\):

Implementation	Runtime
Reference	41.0s
Compiled	2ms

\(n=5000\):

Implementation	Runtime
Reference	123.3s
Compiled	6ms