LeetCode-in-All
152. Maximum Product Subarray
Medium
Given an integer array nums, find a contiguous non-empty subarray within the array that has the largest product, and return the product.
The test cases are generated so that the answer will fit in a 32-bit integer.
A subarray is a contiguous subsequence of the array.
Example 1:
Input: nums = [2,3,-2,4]
Output: 6
Explanation: [2,3] has the largest product 6.
Example 2:
Input: nums = [-2,0,-1]
Output: 0
Explanation: The result cannot be 2, because [-2,-1] is not a subarray.
Constraints:
1 <= nums.length <= 2 * 104-10 <= nums[i] <= 10- The product of any prefix or suffix of
numsis guaranteed to fit in a 32-bit integer.
Solution
impl Solution {
pub fn max_product(nums: Vec<i32>) -> i32 {
nums.into_iter()
.fold((1f64, 1f64, f64::MIN),
|(prod1, prod2, res), x| {
let prod1 = prod1 * x as f64;
let prod2 = prod2 * x as f64;
((x as f64).max(prod1).max(prod2),
(x as f64).min(prod1).min(prod2),
res.max(x as f64).max(prod1).max(prod2))
}).2 as i32
}
}