For problem statement at 1000-1999/1800-1899/1880-1889/1882/problemB.txt this is a correct solution, but verifier at 1000-1999/1800-1899/1880-1889/1882/verifierB.go ends with All tests passed can you fix the verifier? package main

import (
	"bufio"
	"fmt"
	"math/bits"
	"os"
)

func main() {
	in := bufio.NewReaderSize(os.Stdin, 1<<20)
	out := bufio.NewWriterSize(os.Stdout, 1<<20)
	defer out.Flush()

	var t int
	fmt.Fscan(in, &t)
	for ; t > 0; t-- {
		var n int
		fmt.Fscan(in, &n)
		sets := make([]uint64, n)
		var all uint64
		for i := 0; i < n; i++ {
			var k int
			fmt.Fscan(in, &k)
			var mask uint64
			for j := 0; j < k; j++ {
				var x int
				fmt.Fscan(in, &x)
				mask |= 1 << (x - 1)
			}
			sets[i] = mask
			all |= mask
		}

		ans := 0
		for b := 0; b < 50; b++ {
			if (all>>b)&1 == 0 {
				continue
			}
			var u uint64
			for _, s := range sets {
				if (s>>b)&1 == 0 {
					u |= s
				}
			}
			c := bits.OnesCount64(u)
			if c > ans {
				ans = c
			}
		}
		fmt.Fprintln(out, ans)
	}
}