#include <bits/stdc++.h>
using namespace std;
long long n, T, a, b;
long long kq;
char k;
int main() {
  ios_base::sync_with_stdio(false);
  cin >> T;
  for (int t = 1; t <= T; t++) {
    cin >> n >> a >> b;
    char kt = '0';
    int ct = 1;
    long long d[2 * 100005];
    memset(d, 0, sizeof(d));
    for (int i = 1; i <= n; i++) {
      cin >> k;
      if (k == kt)
        d[ct]++;
      else {
        kt = k;
        ct++;
        d[ct]++;
      }
    }
    kq = (d[1] - 1) * a + d[1] * b + 2 * a + 2 * b;
    if (ct == 1) kq = kq - a - b;
    for (int i = 2; i < ct; i++) {
      if (i % 2 == 0) {
        kq += a * (d[i]) + b * 2 * (d[i] - 1);
      } else {
        if (d[i] > 1)
          kq += min(a * 4 + (d[i] - 2) * a + (d[i] - 1 + 4) * b,
                    a * d[i] + b * (d[i] + 1) * 2);
        if (d[i] == 1) kq += a + 4 * b;
      }
    }
    if (ct >= 3) kq += 2 * a + (d[ct] - 1) * a + (d[ct] + 2) * b;
    cout << kq << "\n";
  }
  return 0;
}
