數(shù)組中子數(shù)組下標(biāo)相同的放在同一個(gè)數(shù)組中

let arr = [
      ["1-1", "1-2", "1-3", "1-4", "1-5"],
      ["2-1", "2-2", "2-3", "2-4", "2-5"],
      ["3-1", "3-2", "3-3", "3-4", "3-5"],
      ["4-1", "4-2", "4-3", "4-4", "4-5"],
      ["5-1", "5-2", "5-3", "5-4", "5-5"],
    ];
let newArr = arr[0].map((item, i) => {
      return arr.map((row) => {
        return row[i];
      });
    });