function squish(arr) {
	function accumulate(acc, val, i) {
		if(val === arr[i-1]) {
			let tuple = acc[i-1];
			tuple[1]++;
			acc[i] = tuple
			delete acc[i-1];
		} else {
			acc[i] = [val, 1];
		}
		return acc;
	};
	return arr.reduce(accumulate, []).filter(x=>x!==undefined);
}