If Array Elements have Unique Frequencies

const hasUniqueFrequencies = <T>(array: T[]): boolean => {
    const itemCountMap = new Map<T, number>();

    for (const item of array) {
        const itemCount = itemCountMap.get(item);

        if (itemCount)
            itemCountMap.set(item, itemCount + 1);
        else
            itemCountMap.set(item, 1);
    }

    const countSet = new Set<number>(itemCountMap.values());

    return itemCountMap.size === countSet.size;
}

const array = [2, 2, 3, 3, 3];

console.log(hasUniqueFrequencies(array));