js 根据指定个数切割数组
arr: [
{name: '小明', age: 20},
{name: '小红', age: 21},
{name: '小军', age: 22},
{name: '小王', age: 23},
{name: '小朱', age: 24},
{name: '小刘', age: 25},
{name: '小张', age: 26},
{name: '小庞', age: 27},
{name: '小米', age: 28},
{name: '小华', age: 29},
{name: '小郑', age: 30},
{name: '小蓝', age: 31},
{name: '小绿', age: 32},
{name: '小青', age: 33},
{name: '小白', age: 34},
{name: '小黑', age: 35},
{name: '小橙', age: 36},
{name: '小紫', age: 37},
{name: '小山', age: 38},
{name: '小一', age: 39},
{name: '小鹏', age: 40},
{name: '小丛', age: 41},
{name: '小鱼', age: 42},
{name: '小李', age: 43},
{name: '小英', age: 44},
{name: '小杰', age: 45},
{name: '小金', age: 46},
{name: '小窗', age: 47},
{name: '小叶', age: 48},
{name: '小文', age: 49},
{name: '小龙', age: 50},
{name: '小纯', age: 51},
{name: '小伟', age: 52},
{name: '小佳', age: 53},
{name: '小吴', age: 54},
{name: '小枚', age: 55},
{name: '小原', age: 56},
{name: '小书', age: 57},
{name: '小江', age: 58},
{name: '小砚', age: 59},
{name: '小然', age: 60}
],