#include 
#include 
#include 
#include 
using namespace std;
int n;
int m;

int dp[100005];
vectorgraph[100005];
int rec(int node){
    int result=0;
    if(node==n){
       return 1;
    }
    if(dp[node]!=-1){
        return dp[node];
    }
    int MOD = 1e9 + 7;
    for(int i=0; i>n>>m;
    for(int i=0; i>a>>b;
    graph[a].push_back(b);
    }
    memset(dp, -1, sizeof dp);

    cout<