public int searchInsert(int[] nums, int target) {
            if(nums[0]>=target)return 0;//剪枝
			if(nums[nums.length-1]==target)return nums.length-1;//剪枝
			if(nums[nums.length-1]<target)return nums.length;
			int left=0,right=nums.length-1;
			while (left<right) {
				int mid=(left+right)/2;
				if(nums[mid]==target)
					return mid;
				else if (nums[mid]>target) {
					right=mid;
				}
				else {
					left=mid+1;
				}
			}
			return left;
    }