javascript - 匹配相同值的十进制数以插入数组

Question

我在数组中有一个 Srings

var QNo = ["1.1","1.2","1.3","2.1","2.2","3.1","3.2","3.3","4.1","4.2"];

需要像这样更改具有匹配小数的对象数组中的QNo

var result = [["1.1","1.2","1.3"],["2.1","2.2"],["3.1","3.2","3.3"],["4.1","4.2"]];

我试过这种代码

for (var j = 0; j < QNo.length ; j++) {
     if ( QNo[j].match(/.*(?=\.)/g) ) {
      result.push(QNo[j]);
     }
}

比赛结束后，我不知道将小数值作为对象推送

Answer 1

您可以取出拆分值的左侧部分并检查最后一个值是否在同一组中——然后将该值推送到组中。如果没有，则建立一个新组。

var qNo = ["1.1", "1.2", "1.3", "2.1", "2.2", "3.1", "3.2", "3.3", "4.1", "4.2"],
    result = qNo.reduce(function (r, a, i, aa) {
        function left(a) { return (a || '').split('.')[0]; }
        if (left(a) === left(aa[i - 1])) {
            r[r.length - 1].push(a);
        } else {
            r.push([a]);
        }
        return r;
    }, []);

console.log(result);

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对于未排序的值，您可以使用哈希表并稍后对结果进行排序。

var qNo = ["1.1", "3.1", "1.2", "1.3", "2.1", "3.2", "3.3", "4.1", "2.2", "4.2"],
    hash = Object.create(null),
    result = qNo.reduce(function (r, a, i, aa) {
        function left(a) { return (a || '').split('.')[0]; }
        var key = left(a);
        if (!hash[key]) {
            hash[key] = [];
            r.push(hash[key]);
        }
        hash[key].push(a);
        return r;
    }, []);

console.log(result);

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