A. Buy the Stringtime limit per test1 secondmemory limit per test256 megabytesinputstandard inputoutputstandard outputYou are given four integers n, c_0, c_1 and h and a binary string s of length n.A binary string is a string consisting of characters 0 and 1.You can change any character of the string s (the string should be still binary after the change). You should pay h coins for each change.After some changes (possibly zero) you want to buy the string. To buy the string you should buy all its characters. To buy the character 0 you should pay c_0 coins, to buy the character 1 you should pay c_1 coins.Find the minimum number of coins needed to buy the string.InputThe first line contains a single integer t (1 \leq t \leq 10) — the number of test cases. Next 2t lines contain descriptions of test cases.The first line of the description of each test case contains four integers n, c_{0}, c_{1}, h (1 \leq n, c_{0}, c_{1}, h \leq 1000).The second line of the description of each test case contains the binary string s of length n.OutputFor each test case print a single integer — the minimum number of coins needed to buy the string.ExampleInput
6
3 1 1 1
100
5 10 100 1
01010
5 10 1 1
11111
5 1 10 1
11111
12 2 1 10
101110110101
2 100 1 10
00
Output
3
52
5
10
16
22
NoteIn the first test case, you can buy all characters and pay 3 coins, because both characters 0 and 1 costs 1 coin.In the second test case, you can firstly change 2-nd and 4-th symbols of the string from 1 to 0 and pay 2 coins for that. Your string will be 00000. After that, you can buy the string and pay 5 \cdot 10 = 50 coins for that. The total number of coins paid will be 2 + 50 = 52.
6
3 1 1 1
100
5 10 100 1
01010
5 10 1 1
11111
5 1 10 1
11111
12 2 1 10
101110110101
2 100 1 10
00

3 52 5 10 16 22 
['implementation', 'math', '*800']