#include <bits/stdc++.h>
using namespace std;
int main() {
  string s;
  int num;
  cin >> num;
  cin >> s;
  int ans = 0;
  for (auto i : s) {
    if (i == '+') {
      ans++;
    } else if (i == '-') {
      ans--;
    }
  }
  cout << ans;
  return 0;
}
