679. 24 Game
You have 4 cards each containing a number from 1 to 9. You need to judge whether they could operated through *
, /
, +
, -
, (
, )
to get the value of 24.
Example 1:
Input: [4, 1, 8, 7]
Output: True
Explanation: (8-4) * (7-1) = 24
Example 2:
Input: [1, 2, 1, 2]
Output: False
Note:
- The division operator
/
represents real division, not integer division. For example, 4 / (1 - 2/3) = 12. - Every operation done is between two numbers. In particular, we cannot use
-
as a unary operator. For example, with[1, 1, 1, 1]
as input, the expression-1 - 1 - 1 - 1
is not allowed. - You cannot concatenate numbers together. For example, if the input is
[1, 2, 1, 2]
, we cannot write this as 12 + 12.
# @lc code=start
using LeetCode
function judgePoint24(nums::Vector)::Bool
n = length(nums)
if n == 1
return nums[1] == 24
else
for i in 1:n
for j in 1:n
if j != i
rest = [nums[k] for k in 1:n if k != i && k != j]
if judgePoint24([rest..., nums[i] + nums[j]]) ||
judgePoint24([rest..., nums[i] - nums[j]]) ||
judgePoint24([rest..., nums[j] - nums[i]]) ||
judgePoint24([rest..., nums[i] * nums[j]]) ||
(!iszero(nums[j]) && judgePoint24([rest..., nums[i]//nums[j]])) ||
(!iszero(nums[i]) && judgePoint24([rest..., nums[j]//nums[i]]))
return true
end
end
end
end
false
end
end
# @lc code=end
judgePoint24 (generic function with 1 method)
This page was generated using DemoCards.jl and Literate.jl.