js数组去重，以及获取数组重复元素个数

// 已知arr格式如下，输出info1和info2
var arr = ["2011-1-1","2011-1-1","2011-1-2","2011-1-3","2011-1-2","2011-1-1"]; 
// var info1 = {"2011-1-1": 3, "2011-1-2": 2, "2011-1-3": 1}
// var info2 = [{time: "2011-1-1", count: 3}, {time: "2011-1-2", count: 2},{time: "2011-1-3", count: 1}]

// 数组元素去重
function uniqueArr(arr){
	var x = new Set(arr);
	return [...x];
}

// 获取重复元素个数，输出info1
function getWordCnt(arr){ 
	return arr.reduce(function(prev,next){ 
	    prev[next] = (prev[next] + 1) || 1; 
	    return prev; 
	},{}); 
} 

// 获取重复元素个数，输出info2
var getArrCountInfo = function (arr) {
	var info2 = [];
	uniqueArr(arr).forEach(function(item) {
		var countInfo = {};
		countInfo.time = item;
		countInfo.count = getWordCnt(arr)[item];
		info2.push(countInfo);
	});
	return info2;
}

console.log(getWordCnt(arr));
console.log(getArrCountInfo(arr));