#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define ll long long
#define ld long double
#define ull unsigned long long
#define ff first
#define ss second
#define pii pair<int,int>
#define pll pair<long long, long long>
#define vi vector<int>
#define vl vector<long long>
#define pb push_back
#define rep(i, b) for(int i = 0; i < (b); ++i)
#define rep2(i,a,b) for(int i = a; i <= (b); ++i)
#define rep3(i,a,b,c) for(int i = a; i <= (b); i+=c)
#define count_bits(x) __builtin_popcountll((x))
#define all(x) (x).begin(),(x).end()
#define siz(x) (int)(x).size()
#define forall(it,x) for(auto& it:(x))
using namespace __gnu_pbds;
using namespace std;
typedef tree<int, null_type, less<int>, rb_tree_tag,tree_order_statistics_node_update> ordered_set;
//mt19937 mt;void random_start(){mt.seed(chrono::time_point_cast<chrono::milliseconds>(chrono::high_resolution_clock::now()).time_since_epoch().count());}
//ll los(ll a, ll b) {return a + (mt() % (b-a+1));}
const int INF = 1e9+50;
const ll INF_L = 1e18+40;
const ll MOD = 1e9+7;
int n,m;
ll dp[500001][26];
int first_mom[500001][2];
vl events[500001][2];
vector<pll> add_events[500001];
ll cur_add[26][2];
int main()
{
ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
//random_start();
cin >> n >> m;
rep(i,m)
{
int a,b;
cin >> a >> b;
if(a < b)
{
events[a+1][0].pb(a+1);
events[b+1][0].pb(-(a+1));
}
else
{
events[b+1][1].pb(b+1);
events[a+1][1].pb(-(b+1));
}
}
multiset<int> begs[2];
rep2(i,1,n)
{
rep(d,2)
{
forall(it,events[i][d])
{
if(it > 0) begs[d].insert(it);
else begs[d].erase(begs[d].find(-it));
}
if(siz(begs[d]) != 0)
{
auto it = begs[d].end();
it--;
first_mom[i][d^1] = *it;
}
}
rep(d,2)
{
add_events[first_mom[i][d]].pb({i,d});
}
}
rep2(k,0,25)
{
dp[1][k] = 1;
}
ll ans = 0;
rep2(i,1,n)
{
rep(prv,26)
{
dp[i][prv] += cur_add[prv][0] + cur_add[prv][1];
dp[i][prv] %= MOD;
}
forall(it,add_events[i])
{
rep(prv,26)
{
dp[it.ff][prv] -= cur_add[prv][it.ss] - MOD;
dp[it.ff][prv] %= MOD;
}
}
rep(prv,26)
{
rep2(prv2,0,prv-1)
{
cur_add[prv2][0] += dp[i][prv];
cur_add[prv2][0] %= MOD;
}
rep2(prv2,prv+1,25)
{
cur_add[prv2][1] += dp[i][prv];
cur_add[prv2][1] %= MOD;
}
ans += dp[i][prv];
ans %= MOD;
}
}
cout << ans;
}
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