#include <bits/stdc++.h>
using namespace std;
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  long long test, i, j, xy, flag = 0, n, u, count, d, o1 = 0, o2 = 0, s, e, l,
                            r, x, y, m, z, max1, x1, y1, k, x2, y2, z1, sum, f,
                            min1;
  cin >> test;
  while (test--) {
    x1 = y1 = 0;
    string a;
    cin >> n >> x >> y >> z >> a;
    for (i = 0; i < n; i++) {
      if (a[i] == '0') {
        x1++;
      } else {
        y1++;
      }
    }
    x2 = (x1 * z) + (x1 * y) + (y1 * y);
    y2 = (y1 * z) + (y1 * x) + (x1 * x);
    z1 = x1 * x + y1 * y;
    cout << min(min(x2, y2), z1) << "\n";
  }
  return 0;
}
