#include "bits/stdc++.h"
using namespace std;
#ifdef duc_debug
#include "bits/debug.h"
#else
#define debug(...)
#endif
const int maxn = 5e5 + 5;
const int mod = 1e9 + 7;
int n, m, a[maxn], b[maxn];
int f[maxn][26], g[2][26];
vector<pair<int, int>> ev[maxn];
set<int> st[2];
int add(int x, int y) {
if (y < 0) y += mod;
x = x + y;
if (x >= mod) x -= mod;
return x;
}
void solve() {
cin >> n >> m;
for (int i = 1; i <= m; ++i) {
int x, y; cin >> x >> y;
if (x < y) {
ev[x + 1].emplace_back(y, 1);
} else {
ev[y + 1].emplace_back(x, 0);
}
}
for (int i = 0; i <= n; ++i) {
for (int j = 0; j < 26; ++j) {
f[i][j] = 1;
}
}
auto ins = [&](int p) {
st[0].insert(p);
st[1].insert(p);
for (int i = 0; i < 26; ++i) {
g[0][i] = add(g[0][i], f[p][i]);
g[1][i] = add(g[1][i], f[p][i]);
}
};
auto del = [&](int id, int p) {
while (!st[id].empty() and *st[id].begin() <= p) {
for (int j = 0; j < 26; ++j) {
g[id][j] = add(g[id][j], -f[*st[id].begin()][j]);
}
st[id].erase(st[id].begin());
}
};
ins(n);
for (int i = n - 1; i; --i) {
for (auto [p, id] : ev[i + 1]) {
del(id, p);
}
int sum = 1;
for (int j = 0; j < 26; ++j) {
f[i][j] = sum;
sum = add(sum, g[0][j]);
}
sum = 0;
for (int j = 25; j >= 0; --j) {
f[i][j] = add(f[i][j], sum);
sum = add(sum, g[1][j]);
}
ins(i);
}
int res = 0;
for (int j = 0; j < 26; ++j) {
res = add(res, f[1][j]);
}
cout << res;
}
signed main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
solve();
return 0;
}
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