nm = gets.chomp!.scan(/^(\d+) (\d+)$/)
abort "line 1: format" unless nm.size == 1
n,m = nm[0].map(&:to_i)

line = gets.chomp!
abort "line 2: format" unless line=~/^\d+(?: \d+)*$/
aa = line.split.map(&:to_i)
aa.each{|e|
    abort "line 2: 1<=a<=10^7" unless 1 <= e && e <= 10000000
}

m.times{|no|
    lsc = gets.chomp!.scan(/^(\d+) (\d+)$/)
    abort "line #{no+3}: format" unless lsc.size == 1
    u,v = lsc[0].map(&:to_i)
    abort "line #{no+3}: u < v" unless u < v
    abort "line #{no+3}: 1 <= u <= n" unless 1 <= u && u <= n
    abort "line #{no+3}: 1 <= v <= n" unless 1 <= v && v <= n
}
abort "eof: too many" unless !gets

puts "format ok"