416. Partition Equal Subset Sum

Given a non-empty array `nums` containing only positive integers, find if the array can be partitioned into two subsets such that the sum of elements in both subsets is equal.

Example 1:

```Input: nums = [1,5,11,5]
Output: true
Explanation: The array can be partitioned as [1, 5, 5] and [11].
```

Example 2:

```Input: nums = [1,2,3,5]
Output: false
Explanation: The array cannot be partitioned into equal sum subsets.
```

Constraints:

• `1 <= nums.length <= 200`
• `1 <= nums[i] <= 100`

416. Partition Equal Subset Sum
``````struct Solution;

impl Solution {
fn can_partition(nums: Vec<i32>) -> bool {
let sum: i32 = nums.iter().sum();
if sum % 2 == 1 {
return false;
}
let half = (sum / 2) as usize;
let mut dp: Vec<bool> = vec![false; half as usize + 1];
dp[0] = true;
let mut max = 0;
for x in nums {
let j = x as usize;
for i in (j..=half.min(max + j)).rev() {
if dp[i - j] {
dp[i] = true;
max = max.max(i);
}
}
if dp[half] {
return true;
}
}
false
}
}

#[test]
fn test() {
let nums = vec![1, 5, 11, 5];
let res = true;
assert_eq!(Solution::can_partition(nums), res);
let nums = vec![1, 2, 5];
let res = false;
assert_eq!(Solution::can_partition(nums), res);
}
``````