DP Target sum

	This questions breaks upto the one in which we have two subarrays 
           with a difference d , in this question the given target is the difference 
          if there exists that difference then we have to return the t
	
	class Solution {
	public:
	int func(int ind ,int s1,vector<vector<int>>&dp,vector<int>&arr){
	    // if(s1==0){
	    //     return 1;
	    // }
	    if(ind==0){
	        if(s1==0&&arr[0]==0)return 2;
	        if(s1==0||s1==arr[0])return 1;
	        return 0;
	    }
	    if(dp[ind][s1]!=-1){
	        return dp[ind][s1];
	    }
	    int nottake = func(ind-1,s1,dp,arr);
	    int take = 0;
	    if(s1>=arr[ind]){
	        take = func(ind-1,s1-arr[ind],dp,arr);
	    }
	    return dp[ind][s1]=take+nottake;
	}
	int findTargetSumWays(vector<int> &nums,int target) {
	    int n = nums.size();
	    // Write your code here.
	    int totalsum = 0;
	    for(int i =0;i<nums.size();i++){
	        totalsum+=nums[i];
	    }
	    int s1 = (totalsum-target)/2;
	    if ((totalsum - target) % 2 == 0 && totalsum - target >= 0) {
	        vector<vector<int>> dp(n, vector<int>(s1 + 1, -1));
	        return func(n - 1, s1, dp, nums);
	    }
	    return 0;
	}
	   
};