$2 = 0 while($2 < H * W + 1) $1 = A[$0/W+1,$0%W+1] - B[$0/W+1,$0%W+1] $1 = $1 * $1 + 998244352 $1 = 1 - $1 / 998244353 $0 = $0 + $1 $2 = $2 + 1 end return($0/W+1,$0%W+1)