partition-equal-subset-sum

https://leetcode.com/problems/partition-equal-subset-sum/

public class Solution {
    public boolean canPartition(int[] nums) {
        int sum = 0;
        for (int i=0; i<nums.length; i++) {
            sum += nums[i];
        }

        if (sum % 2 == 1) {
            return false;
        }
        sum /= 2;

        Set st = new HashSet();
        st.add(0);
        for (int i=0; i<nums.length; i++) {
            Set tmpSt = new HashSet();
            Iterator itr = st.iterator();
            while (itr.hasNext()) {
                int newVal = (int)itr.next() + nums[i];
                if (newVal == sum) {
                    return true;
                }
                if (newVal < sum) {
                    tmpSt.add(newVal);
                }
            }
            st.addAll(tmpSt);
        }

        return false;
    }
}