Pirates JS Fundamentals

function pirates(input) {

    let result = {};
    while (input[0] !== 'Sail') {
        let [town, population, gold] = input.shift().split('||')
        population = Number(population);
        gold = Number(gold);
        if (result.hasOwnProperty(town) === false) {

            result[town] = { population, gold }
        } else {
            result[town].population += population;
            result[town].gold += gold;
        }
    }
    let sail = input.shift();
    while (input[0] !== 'End') {
        let tokens = input.shift().split('=>')
        let command = tokens[0];

        if (command === 'Plunder') {
            let city = tokens[1];
            let people = Number(tokens[2]);
            let gold = Number(tokens[3]);
            result[city].population -= people;
            result[city].gold -= gold;
            console.log(`${city} plundered! ${gold} gold stolen, ${people} citizens killed.`);
            if (result[city].population === 0 || result[city].gold === 0) {
                console.log(`${city} has been wiped off the map!`);
                delete result[city];
            }
        } else if (command === 'Prosper') {
            let city = tokens[1];
            let gold = Number(tokens[2]);
            if (gold < 0) {
                console.log(`Gold added cannot be a negative number!`);
            } else {
                result[city].gold += gold;
                console.log(`${gold} gold added to the city treasury. ${city} now has ${result[city].gold} gold.`);
            }
        }
    }
    let str = Object.entries(result);

    if (str.length === 0) {
        console.log(`Ahoy, Captain! All targets have been plundered and destroyed!`);
    } else {
        console.log(`Ahoy, Captain! There are ${str.length} wealthy settlements to go to:`);
        for (let el of str) {

            console.log(`${el[0]} -> Population: ${el[1].population} citizens, Gold: ${el[1].gold} kg`);
        }
    }
}