#include <bits/stdc++.h>
using namespace std;
long long int dp[2 * 100007][3];
long long int n, pipe, pillar;
string s;
long long int solve(long long int state, long long int h) {
  if (state == n) return h == 1 ? pillar : 1LL << 45;
  long long int &ret = dp[state][h];
  if (ret != 1LL << 45) return ret;
  long long int mini = 0;
  if (h == 1) {
    if (s[state] == '1' or s[state + 1] == '1') {
      mini = pillar + (pipe << 1) + solve(state + 1, h + 1);
    } else {
      mini = pillar + min((pipe << 1) + solve(state + 1, h + 1),
                          pipe + solve(state + 1, h));
    }
  } else if (h == 2) {
    if (s[state] == '1' or s[state + 1] == '1') {
      mini = (pillar << 1) + pipe + solve(state + 1, h);
    } else {
      mini = (pillar << 1) + min((pipe << 1) + solve(state + 1, h - 1),
                                 pipe + solve(state + 1, h));
    }
  }
  return ret = mini;
}
void resett(long long int upto) {
  long long int i, j;
  for (i = 0; i < upto + 1; i++) {
    for (j = 1; j < 3; j++) dp[i][j] = 1LL << 45;
  }
}
int main() {
  long long int t, i;
  ios::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  resett(2 * 100007 - 3);
  cin >> t;
  while (t--) {
    cin >> n >> pipe >> pillar >> s;
    s += "0";
    cout << solve(0, 1) << endl;
    resett(n);
  }
  return 0;
}
