def max( x )
	max_value = x[ 0 ]
	(1..x.length-1).each { |i|
		if max_value < x[ i ] then
			max_value = x[ i ]
		end
	}
	return max_value
end

a = [ 5 , 6 , 2 , 3 , 10 , 7 ]
printf( "最大値は%dです\n" , max( a ) )