#include <bits/stdc++.h>
using namespace std;
const long long BINF = 1e18 + 10;
signed main() {
  ios_base::sync_with_stdio(false);
  long long T;
  cin >> T;
  while (T--) {
    long long n, a, b;
    cin >> n >> a >> b;
    vector<long long> c(n);
    for (auto &it : c) {
      char kek;
      cin >> kek;
      it = kek - '0';
    }
    vector<vector<long long>> dp(n + 1, vector<long long>(2, BINF));
    dp[0][0] = b;
    for (long long i = 0; i < n; i++) {
      dp[i + 1][1] = min(dp[i][0] + 2 * (a + b), dp[i][1] + a + 2 * b);
      if (!c[i] && (i + 1 == n || !c[i + 1])) {
        dp[i + 1][0] = min(dp[i][0] + a + b, dp[i][1] + 2 * a + b);
      }
    }
    cout << dp[n][0] << '\n';
  }
}
