#include <iostream>
#include <vector>
#include <numeric>


using namespace std;
int main(){
  vector<int> a(10,1);
  adjacent_difference(a.begin(), std::prev(a.end()), std::next(a.begin()), std::plus<> {});
  copy(a.begin(), a.end(), std::ostream_iterator<int> {std::cout, " "});
  cout << endl;
  vector<int> b{0,2,5,4,2};
  adjacent_difference(b.begin(), std::prev(b.end()), next(b.begin()) , std::plus<> {});
  copy(b.begin(), b.end(), std::ostream_iterator<int> {std::cout, " "});
  return 0;
}

1 1 2 3 5 8 13 21 34 55
0 0 0 0 0
Process finished with exit code 0