#include <bits/stdc++.h>
using namespace std;
const long long N = 2e5 + 10;
long long dp[2][N];
const long long inf = 1e18;
void min_self(long long& a, long long b) { a = min(a, b); }
template <class c>
struct rge {
  c b, e;
};
template <class c>
rge<c> range(c i, c j) {
  return rge<c>{i, j};
}
template <class c>
auto dud(c* x) -> decltype(cerr << *x, 0);
template <class c>
char dud(...);
struct debug {
  ~debug() { cerr << endl; }
  template <class c>
  typename enable_if<sizeof dud<c>(0) != 1, debug&>::type operator<<(c i) {
    cerr << boolalpha << i;
    return *this;
  }
  template <class c>
  typename enable_if<sizeof dud<c>(0) == 1, debug&>::type operator<<(c i) {
    return *this << range(begin(i), end(i));
  }
  template <class c, class b>
  debug& operator<<(pair<b, c> d) {
    return *this << "(" << d.first << ", " << d.second << ")";
  }
  template <class c>
  debug& operator<<(rge<c> d) {
    *this << "[";
    for (auto it = d.b; it != d.e; ++it) *this << ", " + 2 * (it == d.b) << *it;
    return *this << "]";
  }
};
void solve() {
  long long n, a, b;
  cin >> n >> a >> b;
  string s;
  cin >> s;
  for (long long i = 0; i < 2; i++) {
    for (long long j = 0; j <= n; j++) {
      dp[i][j] = inf;
    }
  }
  for (long long i = 0; i < n; i++) {
    if (s[i] == '0' && i + 1 < n && s[i + 1] == '1') {
      min_self(dp[1][i], (i - 1 >= 0 ? dp[0][i - 1] : b) + a + a + 2 * b);
      min_self(dp[1][i], (i - 1 >= 0 ? dp[1][i - 1] : inf) + a + 2 * b);
    } else if (s[i] == '0') {
      min_self(dp[0][i], (i - 1 >= 0 ? dp[1][i - 1] : 2 * b) + a + a + b);
      min_self(dp[0][i], (i - 1 >= 0 ? dp[0][i - 1] : b) + a + b);
      min_self(dp[1][i], (i - 1 >= 0 ? dp[0][i - 1] : b) + a + a + 2 * b);
      min_self(dp[1][i], (i - 1 >= 0 ? dp[1][i - 1] : inf) + a + 2 * b);
    } else {
      min_self(dp[1][i], (i - 1 >= 0 ? dp[0][i - 1] : b) + a + a + 2 * b);
      min_self(dp[1][i], (i - 1 >= 0 ? dp[1][i - 1] : inf) + a + 2 * b);
    }
  }
  cout << dp[0][n - 1] << "\n";
}
int32_t main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  long long t = 1;
  cin >> t;
  for (long long tt = 1; tt <= t; tt++) {
    solve();
  }
}
