<?php
trim(fscanf(STDIN,"%d %d",$N,$M));
$a = -1;
$db = array();
$c =0;
if($c < $M){
        $a= trim(fgets(STDIN));
}
for($j = 0;$j<$N+1;$j++){
        if($j == $a){
                $db[$j] = 0;
                $c++;
                if($c < $M){
                $a= trim(fgets(STDIN));
                }
                }
        elseif($j == 0){
                $db[$j] = 1;
        }
        elseif($j == 1){
        $db[$j] = 1;
        }
        elseif($j > 1){

        $db[$j] = $db[$j-1] + $db[$j-2];
        }

}

echo $db[$N]%1000000007;
?>