function solve(arr) {
    let chat = [];

    for (let line of arr) {
        let tokens = line.split(' ');
        let command = tokens[0];
        let message = tokens[1];

        if (command === 'Chat') {
            chat.push(message);
        } else if (command === 'Delete') {
            chat = chat.filter(x => x !== message);
        } else if (command === 'Edit') {
            let newMessage = tokens[2];
            chat.map((x, i, chat) => x === message ? chat[i] = newMessage : chat[i] = x);
        } else if (command === 'Pin') {
            let messagesToPin = chat.filter(x => x === message);
            chat = chat.filter(x => x !== message);
            chat.push(...messagesToPin);
        } else if (command === 'Spam') {
            chat.push(...tokens.slice(1));
        }
    }

    console.log(chat.join('\n'));
}