class Solution {
public:
    int singleElement(vector<int>& v) {
        int count=0;
        for(int i=0;i<v.size();i++){
            count=0;
             for(int j=0;j<v.size();j++){
                if(v[i]==v[j])
                    count++;
             }
             if(count==1){
                return v[i];
             }
        }
      return -1;
    }
};