// #undef DEBUG
#include <bits/stdc++.h>
using i64 = long long;
#ifdef DEBUG
#include "debug.h"
#else
#define debug(...) void(23)
#endif
constexpr int md = int(1E9) + 7;
struct MInt {
int val;
MInt() : val(0) {}
template<typename T>
MInt(T x) {
if (-md <= x && x < md) {
val = x;
} else {
val = x % md;
}
if (val < 0) {
val += md;
}
}
int operator()() { return val; }
MInt& operator+= (MInt rhs) {
if ((val += rhs.val) >= md) {
val -= md;
}
return *this;
}
MInt& operator-= (MInt rhs) {
if ((val -= rhs.val) < 0) {
val += md;
}
return *this;
}
MInt& operator*= (MInt rhs) {
val = int((1LL * val * rhs.val) % md);
return *this;
}
};
MInt operator+ (MInt lhs, MInt rhs) {
return lhs += rhs;
}
MInt operator- (MInt lhs, MInt rhs) {
return lhs -= rhs;
}
MInt operator* (MInt lhs, MInt rhs) {
return lhs *= rhs;
}
std::ostream& operator<< (std::ostream& os, MInt x) {
return os << x.val;
}
std::string to_string(MInt x) {
return to_string(x.val);
}
using Z = MInt;
int main() {
std::ios_base::sync_with_stdio(false);
std::cin.tie(nullptr);
int N, M;
std::cin >> N >> M;
std::vector<std::array<int, 2>> nxt(N, {-1, -1});
for (int i = 0; i < M; ++i) {
int A, B;
std::cin >> A >> B;
--A, --B;
int tp = 0;
if (A > B) {
tp = 1;
std::swap(A, B);
}
nxt[A][tp] = std::max(nxt[A][tp], B);
}
std::vector<std::array<Z, 26>> dp(N);
for (int i = 0; i < N; ++i) {
for (int j = 0; j < 26; ++j) {
dp[i][j] = 1;
}
}
std::array<Z, 26> sum_sma {}, sum_big {};
std::array<std::vector<int>, 26> ali_sma, ali_big;
for (int i = N - 1; i >= 0; --i) {
for (int c = 0; c < 26; ++c) {
while (!ali_sma[c].empty() && ali_sma[c].back() <= nxt[i][0]) {
for (int oc = 0; oc < c; ++oc) {
sum_sma[c] -= dp[ali_sma[c].back()][oc];
}
ali_sma[c].pop_back();
}
while (!ali_big[c].empty() && ali_big[c].back() <= nxt[i][1]) {
for (int oc = c + 1; oc < 26; ++oc) {
sum_big[c] -= dp[ali_big[c].back()][oc];
}
ali_big[c].pop_back();
}
}
for (int c = 0; c < 26; ++c) {
dp[i][c] += sum_sma[c];
dp[i][c] += sum_big[c];
}
for (int c = 0; c < 26; ++c) {
ali_sma[c].emplace_back(i);
for (int oc = 0; oc < c; ++oc) {
sum_sma[c] += dp[i][oc];
}
ali_big[c].emplace_back(i);
for (int oc = c + 1; oc < 26; ++oc) {
sum_big[c] += dp[i][oc];
}
}
}
Z ans = 0;
for (int i = 0; i < 26; ++i) {
ans += dp[0][i];
}
std::cout << ans << '\n';
return 0;
}
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