#include <bits/stdc++.h>   using namespace std;   int main() {     ios_base::sync_with_stdio(false), cin.tie(NULL), cout.tie(NULL);     int t;     cin >> t;     while (t--) {       int n, c0, c1, h;       cin >> n >> c0 >> c1 >> h;       string binary;       cin >> binary;       int count0 = 0, count1 = 0;       int ans = 0, arbans = 0;       for (auto i = 0; i < binary.length(); i++) {         if (binary[i] ==  1 ) count1++;         if (binary[i] ==  0 ) count0++;       }       arbans = count1 * c1 + count0 * c0;       if (c1 > c0 && c1 > h) {         ans = count1 * h + count0 * c0 + count1 * c0;       } else if (c1 < c0 && c0 > h) {         ans = count0 * h + count1 * c1 + count0 * c1;       } else {         ans = count0 * c0 + count1 * c1;       }       ans = (ans < arbans) ? ans : arbans;       cout << ans << endl;     }     return 0;   }   