1. const canJump = (nums) => {
    2.     let n = nums.length;
    3.     let rightmost = 0;
    4.     for (let i = 0; i < n; ++i) {
    5.         if (i <= rightmost) {
    6.             rightmost = Math.max(rightmost, i + nums[i]);
    7.             if (rightmost >= n - 1) {
    8.                 return true;
    9.             }
    10.         }
    11.     }
    12.     return false;
    13. }