after motiz

sqrt_10000.pl

my Int $i = 2 * 10 ** 20_002;
my Int $sqrt = 10 ** 10_001;
my Int $next_sqrt = ($i div $sqrt + $sqrt) div 2;

repeat {
    $sqrt = $next_sqrt;
    $next_sqrt = ($i div $sqrt + $sqrt) div 2;
}   until $sqrt == $next_sqrt;


say $sqrt.Str.substr(1,*-2);
say $sqrt.Str.chars;