#include <bits/stdc++.h>
using namespace std;
const int MOD = 1e9 + 7;
int add (int a, int b) {
a += b; if (a >= MOD) a -= MOD;
return a;
}
int sub (int a, int b) {
a -= b; if (a < 0) a += MOD;
return a;
}
int mul (int a, int b) {
return (a * 1ll * b) % MOD;
}
int dp[300][300][27][2];
int n, m;
vector <pair <int, int>> dd[300];
int ans (int pos, int prev, int c, int x) {
int &ret = dp[pos][prev][c][x];
if (ret != -1) return ret;
bool flag = 1;
for (auto j : dd[pos]) {
if (j.second == 0) {
flag &= (prev >= j.first || x == 0);
} else {
flag &= (prev >= j.first || x == 1);
}
}
if (!flag) return ret = 0;
if (pos == 0) return ret = 1;
ret = ans(pos - 1, prev, c, x);
for (int i = 0; i < c; i++) {
ret = add(ret, ans(pos - 1, pos, i, 0));
}
for (int i = c + 1; i < 26; i++) {
ret = add(ret, ans(pos - 1, pos, i, 1));
}
return ret;
}
int main () {
memset(dp, -1, sizeof(dp));
cin >> n >> m;
for (int i = 1; i <= m; i++) {
int a, b;
cin >> a >> b;
int l = min(a, b), r = max(a, b);
if (a > b) {
dd[l - 1].push_back({r, 0});
} else {
dd[l - 1].push_back({r, 1});
}
}
int sum = 0;
for (int i = 0; i < 26; i++) {
sum = add(sum, ans(n - 1, n + 1, i, 0));
}
cout << sum << '\n';
}
