QUESTION:
There is a function signFunc(x) that returns:
1 if x is positive. -1 if x is negative. 0 if x is equal to 0. You are given an integer array nums. Let product be the product of all values in the array nums.
Return signFunc(product).
Example 1:
Input: nums = [-1,-2,-3,-4,3,2,1]
Output: 1
Explanation: The product of all values in the array is 144, and signFunc(144) = 1
Example 2:
Input: nums = [1,5,0,2,-3]
Output: 0
Explanation: The product of all values in the array is 0, and signFunc(0) = 0
Example 3:
Input: nums = [-1,1,-1,1,-1]
Output: -1
Explanation: The product of all values in the array is -1, and signFunc(-1) = -1
Constraints:
1 <= nums.length <= 1000
-100 <= nums[i] <= 100
EXPLANATION:
比较简单的题目, 如果有0直接返回0即可, 否则用1或者-1来防止产生的溢出问题.
SOLUTION:
class Solution {
func arraySign(_ nums: [Int]) -> Int {
var result: Int = 1
for num in nums {
if num == 0 {
return 0
} else if num > 0 {
result *= 1
} else if num < 0 {
result *= -1
}
}
return result
}
}