partition equal subset sum

Author: chen0040

.idea/workspace.xml

@@ -426,3 +426,4 @@ codes may not be optimized
 ### Day 21 - Medium
 
 1. [Largest Divisible Subset](https://leetcode.com/problems/largest-divisible-subset/description/)
+1. [Partition Equal Subset Sum](https://leetcode.com/problems/partition-equal-subset-sum/description/)

README.md

@@ -0,0 +1,35 @@
+package com.github.chen0040.leetcode.day21.medium;
+
+
+import java.util.Arrays;
+
+
+/**
+ * Created by xschen on 16/8/2017.
+ *
+ * link: https://leetcode.com/problems/partition-equal-subset-sum/description/
+ */
+public class PartitionEqualSubsetSum {
+   public class Solution {
+      public boolean canPartition(int[] nums) {
+         if(nums.length == 1) return false;
+         Arrays.sort(nums);
+         int sum = 0;
+         for(int i=0; i < nums.length; ++i){
+            sum+=nums[i];
+         }
+         if(sum % 2 == 1) return false;
+         sum /= 2;
+         boolean[] dp = new boolean[sum+1];
+         dp[0] = true;
+         for(int i = 1; i < nums.length; ++i) {
+            for(int j=sum; j >= nums[i-1]; j--) {
+               dp[j] = dp[j] || dp[j - nums[i-1]];
+            }
+         }
+
+         return dp[sum];
+
+      }
+   }
+}