计算数组中的重复项 [英] Count duplicates in an array
本文介绍了计算数组中的重复项的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!
问题描述
我正在尝试显示我的数组的内容,但是存在重复项的地方只需打印名称和数字,例如
I'm trying to display the contents of my array but where duplicates exist just print the name and the number e.g
myArr = ['apple', 'apple', 'orange', 'apple', 'banana', 'orange', 'pineapple']
会显示;
apple 3
orange 2
banana
pineapple
到目前为止,我将它们全部作为字符串返回:
So far I'm returning them all as a string:
arrList = myArr.join(', ');
arrList.toString()
推荐答案
漫长的路
var elements = ["apple", "apple", "orange", "apple", "banana"];
elements.sort();
var current = null;
var count = 0;
for(var i = 0; i < elements.length; i++)
{
if(elements[i] != current)
{
if(count > 0)
{
document.write(current + " " + count + "<br/>");
}
current = elements[i];
count = 1;
}
else
{
count++;
}
}
if(count > 0)
{
document.write(current + " " + count);
短路
var elements = ["apple", "apple", "orange", "apple", "banana"];
var counts = {};
elements.forEach(function(x) {
counts[x] = (counts[x] || 0) + 1;
});
document.write("Apple: " + counts.apple + "<br/>");
document.write("Banana: " + counts.banana + "<br/>");
document.write("Orange: " + counts.orange + "<br/>");
这篇关于计算数组中的重复项的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!
查看全文