int Solution::solve(vector<int> &A) {
    int odd = 0, even = 0, total_even = 0, total_odd = 0;
    for(int i = 0 ; i < A.size() ; i++){
        if(i%2 == 0)
            total_even += A[i];
        else
            total_odd  += A[i];
    }
    int res = 0;
    for(int i = 0 ; i < A.size() ; i++){
        if(i%2==0){
            if(total_even - A[i] - even + odd == total_odd - odd + even)
                res++;
            even += A[i];
        }
        else{
            if(total_even - even + odd == total_odd - A[i] - odd + even)
                res++;
            odd += A[i];
        }
    }
    return res;
}