#include <iostream>
#include <vector>
#include <algorithm>
#include <cassert>
using ll = long long;
#define debug(x) #x << " = " << x << '\n'
const int mod = 1e9 + 7;
const int MAXN = 200;
const int SIGMA = 26;
int dp[MAXN + 1][SIGMA];
int main() {
std::ios_base::sync_with_stdio(false);
std::cin.tie(0);
int n, m;
std::cin >> n >> m;
std::vector<std::vector<int>> gpos(n + 2), gneg(n + 2);
for (int i = 0; i < m; i++) {
int a, b;
std::cin >> a >> b;
if (a < b) {
gneg[a + 1].push_back(b);
} else if (b < a) {
gpos[b + 1].push_back(a);
}
}
std::vector<int> fpos(n + 1, 0);
std::vector<int> fneg(n + 1, 0);
for (int i = n; i > 0; i--) {
for (int x = 0; x < SIGMA; x++) {
dp[i][x] = 1;
}
for (int j : gpos[i + 1]) {
for (int p = i + 1; p <= j; p++) {
fpos[p]++;
}
}
for (int j : gneg[i + 1]) {
for (int p = i + 1; p <= j; p++) {
fneg[p]++;
}
}
for (int j = i + 1; j <= n; j++) {
if (!fpos[j] || !fneg[j]) {
if (!fpos[j] && !fneg[j]) { // fac orice
for (int x = 0; x < SIGMA; x++) {
for (int y = 0; y < SIGMA; y++) {
if (x != y) {
dp[i][x] += dp[j][y];
dp[i][x] %= mod;
}
}
}
} else {
if (!fpos[j]) {
for (int x = 0; x < SIGMA; x++) {
for (int y = x + 1; y < SIGMA; y++) {
dp[i][x] += dp[j][y];
dp[i][x] %= mod;
}
}
} else {
for (int x = 0; x < SIGMA; x++) {
for (int y = 0; y < x; y++) {
dp[i][x] += dp[j][y];
dp[i][x] %= mod;
}
}
}
}
}
}
}
ll answer = 0;
for (int i = 0; i < SIGMA; i++) {
answer += dp[1][i];
}
std::cout << answer % mod;
return 0;
}
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