#include <bits/stdc++.h>
using namespace std;
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  int t;
  cin >> t;
  while (t--) {
    long long n, a, b;
    cin >> n >> a >> b;
    vector<vector<long long>> dp(2, vector<long long>(n, 0));
    vector<char> s(n);
    cin >> s[0];
    dp[1][0] = 1000000000000000;
    for (int i = 1; i < n; ++i) {
      cin >> s[i];
      dp[0][i] = min(dp[0][i - 1], dp[1][i - 1] + a);
      dp[1][i] = min(dp[0][i - 1] + a + b, dp[1][i - 1] + b);
      if (s[i] == '1' || s[i - 1] == '1') dp[0][i] = 1000000000000000;
    }
    cout << min(dp[0][n - 1], dp[1][n - 1] + a) + (a + b) * n + b << '\n';
  }
}
