【JAVA】：彻底搞懂重写、重载、多态、向上转型、向下转型

@衡: public int[] searchRange(int[] nums, int target) { int[] ans={-1,-1}; if(nums.length==0){ return ans;//为空，即无目标值，直接返回 } int left = 0,right = nums.length-1; int mid = (left + right)/2; //缩小范围 while(left =left){ if(nums[left] == target){ ans[0] = left; break; } left++; } while(right>=left){ if(nums[right] == target){ ans[1] = right; break; } right--; } return ans; }