高精度
java做
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import java.io.*;
import java.util.*;
import java.math.*;
public class Main {
static public void main(String[] args)
{
Scanner cin = new Scanner(new BufferedInputStream(System.in));
int t = cin.nextInt();
while (t-- != 0)
{
int a = cin.nextInt();
String s = cin.next();
char ch = s.charAt(0);
BigInteger ans = new BigInteger("1");
for (int i = 2; i <= a; i++)
ans = ans.multiply(BigInteger.valueOf(i));
s = ans.toString();
int len = s.length();
int x = 0;
for (int i = 0; i < len; i++)
if (s.charAt(i) == ch)
x++;
System.out.println(x);
}
}
}