For problem statement at 1000-1999/1200-1299/1200-1209/1201/problemE2.txt this is a correct solution, but verifier at 1000-1999/1200-1299/1200-1209/1201/verifierE2.go ends with Problem E2 is interactive and cannot be automatically verified. can you fix the verifier? package main

import (
	"bufio"
	"fmt"
	"io"
	"os"
)

const (
	Draw  uint8 = 0
	White uint8 = 1
	Black uint8 = 2
)

var (
	n, m int
	N    int
	NN   int

	moves   [][]int
	moveCnt []uint8

	wTarget int
	bTarget int

	isW    []bool
	isB    []bool
	attW   []bool
	attB   []bool
	result []uint8
	rem    []uint8
)

func idx(turn, w, b int) int {
	return turn*NN + w*N + b
}

func decode(id int) (int, int, int) {
	turn := 0
	if id >= NN {
		turn = 1
		id -= NN
	}
	w := id / N
	b := id % N
	return turn, w, b
}

func terminal(turn, w, b int) uint8 {
	if w == b {
		if turn == 0 {
			return Black
		}
		return White
	}
	sw := isW[w] && !attW[b]
	sb := isB[b] && !attB[w]
	if sw && sb {
		if turn == 0 {
			return Black
		}
		return White
	}
	if sw {
		return White
	}
	if sb {
		return Black
	}
	return Draw
}

func initialWinner(w, b int) uint8 {
	sw := isW[w] && !attW[b]
	sb := isB[b] && !attB[w]
	if sw && !sb {
		return White
	}
	if sb && !sw {
		return Black
	}
	if sw && sb {
		return White
	}
	if w == b {
		return White
	}
	return Draw
}

func buildMoves() {
	dx := [8]int{1, 1, -1, -1, 2, 2, -2, -2}
	dy := [8]int{2, -2, 2, -2, 1, -1, 1, -1}
	moves = make([][]int, N)
	moveCnt = make([]uint8, N)
	isW = make([]bool, N)
	isB = make([]bool, N)
	attW = make([]bool, N)
	attB = make([]bool, N)

	isW[wTarget] = true
	isB[bTarget] = true

	for r := 0; r < n; r++ {
		for c := 0; c < m; c++ {
			p := r*m + c
			list := make([]int, 0, 8)
			for k := 0; k < 8; k++ {
				nr := r + dx[k]
				nc := c + dy[k]
				if nr >= 0 && nr < n && nc >= 0 && nc < m {
					q := nr*m + nc
					list = append(list, q)
					if q == wTarget {
						attW[p] = true
					}
					if q == bTarget {
						attB[p] = true
					}
				}
			}
			moves[p] = list
			moveCnt[p] = uint8(len(list))
		}
	}
}

func solve() {
	total := 2 * NN
	result = make([]uint8, total)
	rem = make([]uint8, total)
	queue := make([]int32, 0, total/8+1)

	for w := 0; w < N; w++ {
		lw := moveCnt[w]
		base0 := w * N
		base1 := NN + w*N
		for b := 0; b < N; b++ {
			id0 := base0 + b
			t0 := terminal(0, w, b)
			if t0 != Draw {
				result[id0] = t0
				queue = append(queue, int32(id0))
			} else if lw == 0 {
				result[id0] = Black
				queue = append(queue, int32(id0))
			} else {
				rem[id0] = lw
			}

			id1 := base1 + b
			t1 := terminal(1, w, b)
			lb := moveCnt[b]
			if t1 != Draw {
				result[id1] = t1
				queue = append(queue, int32(id1))
			} else if lb == 0 {
				result[id1] = White
				queue = append(queue, int32(id1))
			} else {
				rem[id1] = lb
			}
		}
	}

	for head := 0; head < len(queue); head++ {
		s := int(queue[head])
		g := result[s]
		turn, w, b := decode(s)

		if turn == 0 {
			base := NN + w*N
			for _, bp := range moves[b] {
				p := base + bp
				if result[p] != Draw {
					continue
				}
				if g == Black {
					result[p] = Black
					queue = append(queue, int32(p))
				} else {
					rem[p]--
					if rem[p] == 0 {
						result[p] = White
						queue = append(queue, int32(p))
					}
				}
			}
		} else {
			for _, wp := range moves[w] {
				p := wp*N + b
				if result[p] != Draw {
					continue
				}
				if g == White {
					result[p] = White
					queue = append(queue, int32(p))
				} else {
					rem[p]--
					if rem[p] == 0 {
						result[p] = Black
						queue = append(queue, int32(p))
					}
				}
			}
		}
	}
}

func better(my, a, b uint8) bool {
	if a == b {
		return false
	}
	if my == White {
		if a == White {
			return true
		}
		if a == Draw && b == Black {
			return true
		}
		return false
	}
	if a == Black {
		return true
	}
	if a == Draw && b == White {
		return true
	}
	return false
}

func chooseMove(turn, w, b int, my uint8) (int, bool) {
	bestPos := -1
	bestRes := uint8(0)

	if turn == 0 {
		for _, nw := range moves[w] {
			r := terminal(1, nw, b)
			if r == Draw {
				r = result[idx(1, nw, b)]
			}
			if bestPos == -1 || better(my, r, bestRes) {
				bestPos = nw
				bestRes = r
				if r == my {
					break
				}
			}
		}
	} else {
		for _, nb := range moves[b] {
			r := terminal(0, w, nb)
			if r == Draw {
				r = result[idx(0, w, nb)]
			}
			if bestPos == -1 || better(my, r, bestRes) {
				bestPos = nb
				bestRes = r
				if r == my {
					break
				}
			}
		}
	}

	if bestPos == -1 {
		return 0, false
	}
	return bestPos, true
}

func printPos(out *bufio.Writer, p int) {
	fmt.Fprintln(out, p/m+1, p%m+1)
	out.Flush()
}

func main() {
	in := bufio.NewReader(os.Stdin)
	out := bufio.NewWriter(os.Stdout)
	defer out.Flush()

	var x1, y1, x2, y2 int
	if _, err := fmt.Fscan(in, &n, &m, &x1, &y1, &x2, &y2); err != nil {
		if err == io.EOF {
			return
		}
		return
	}

	N = n * m
	NN = N * N

	wTarget = (n/2-1)*m + (m/2 - 1)
	bTarget = (n / 2 * m) + (m/2 - 1)

	w := (x1-1)*m + (y1 - 1)
	b := (x2-1)*m + (y2 - 1)

	buildMoves()
	solve()

	my := initialWinner(w, b)
	if my == Draw {
		my = result[idx(0, w, b)]
	}
	if my == Draw {
		my = White
	}

	if my == White {
		fmt.Fprintln(out, "White")
	} else {
		fmt.Fprintln(out, "Black")
	}
	out.Flush()

	if initialWinner(w, b) != Draw {
		return
	}

	turn := 0

	for {
		if (turn == 0 && my == White) || (turn == 1 && my == Black) {
			npos, ok := chooseMove(turn, w, b, my)
			if !ok {
				return
			}
			if turn == 0 {
				w = npos
			} else {
				b = npos
			}
			printPos(out, npos)
			turn ^= 1
			if terminal(turn, w, b) != Draw {
				return
			}
		} else {
			var xr, yr int
			if _, err := fmt.Fscan(in, &xr, &yr); err != nil {
				return
			}
			if xr < 0 || yr < 0 {
				return
			}
			p := (xr-1)*m + (yr - 1)
			if turn == 0 {
				w = p
			} else {
				b = p
			}
			turn ^= 1
			if terminal(turn, w, b) != Draw {
				return
			}
		}
	}
}