416. Partition Equal Subset Sum

Given a non-empty array 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.

Note:

Each of the array element will not exceed 100.
The array size will not exceed 200.

Example 1:

Input: [1, 5, 11, 5]

Output: true

Explanation: The array can be partitioned as [1, 5, 5] and [11].

Example 2:

Input: [1, 2, 3, 5]

Output: false

Explanation: The array cannot be partitioned into equal sum subsets.

这是一道很典型的dp问题，我的做法是先求得所给数组的和，然后将和除一半，就变成了背包问题，然后直接dp求解。代码如下：

class Solution {
public:
bool canPartition(vector<int>& nums) {
int sum=0;
for(int i=0;i<nums.size();i++)
sum+=nums[i];
if(sum%2==1)    return 0;
sum/=2;
bool *get = new bool [sum+1];
get[0]=1;
for(int i=1;i<=sum;i++)
get[i]=0;
for(int i=0;i<nums.size();i++)
for(int j=sum;j>=nums[i];j--)
get[j] = get[j-nums[i]] ? 1:get[j];

return get[sum];
}
};