//統計數組內重復元素的個數
const arr = ["leyi", "leyi", "leyi2", "leyi2", "leyi3", "leyi4", "leyi5"];
const statInfo = [];
for (let i = 0; i < arr.length;) {
    let count = 0;
    for (let j = i; j < arr.length; j++) {
        if (arr[i] == arr[j]) {
            count++;
        }
    }
    statInfo.push({name: arr[i], count: count});
    i += count
}
console.info(statInfo);

//二維數組排序(根據數組裏第二個元素排序)
const tdimensionArr = [["c", 3], ["b", 2], ["a", 1], ["e", 5], ["d", 4]];
const sorTdimensionArr = tdimensionArr.sort(((a, b) = > (a[1] - b[1])));
console.info(sorTdimensionArr);

//求輸出結果
function Foo() {
    getName = function () {
        console.info(1);
    };
    return this;
}
Foo.getName = function () {
    console.info(2);
};
Foo.prototype.getName = function () {
    console.info(3);
};
var getName = function () {
    console.info(4);
};
function getName() {
    console.info(5);
}

Foo.getName(); //2
getName(); //4
Foo().getName(); //1
getName();//1
new Foo.getName();//2
new Foo().getName();//3
new new Foo().getName();//3

源文章鏈接 http://www.cnblogs.com/xxcanghai/p/5189353.html　　

知識點筆記（二維數組排序、統計數組重復個數、）