// need
#include <iostream>
#include <algorithm>
// data structure
#include <bitset>
#include <map>
#include <queue>
#include <set>
#include <stack>
#include <string>
#include <utility>
#include <vector>
#include <complex>
//#include <deque>
#include <valarray>
#include <unordered_map>
#include <array>
// stream
//#include <istream>
#include <sstream>
//#include <ostream>
#include <fstream>
// etc
#include <cassert>
#include <cmath>
#include <functional>
#include <iomanip>
//#include <chrono>
#include <random>
#include <numeric>

namespace mystd {
	int stoi(std::string s) {
		std::stringstream ss(s);
		int res = 0;
		ss >> res;
		return res;
	}
	long long stoll(std::string s) {
		std::stringstream ss(s);
		long long res = 0;
		ss >> res;
		return res;
	}
	template<class T>
	std::string to_string(T d) {
		std::stringstream ss;
		ss << d;
		std::string res;
		ss >> res;
		return res;
	}
}

// input
#define INIT std::ios::sync_with_stdio(false);std::cin.tie(0);
#define VAR(type, ...)type __VA_ARGS__;MACRO_VAR_Scan(__VA_ARGS__);
template<typename T> void MACRO_VAR_Scan(T& t) { std::cin >> t; }
template<typename First, typename...Rest>void MACRO_VAR_Scan(First& first, Rest&...rest) { std::cin >> first; MACRO_VAR_Scan(rest...); }
#define VEC_ROW(type, n, ...)std::vector<type> __VA_ARGS__;MACRO_VEC_ROW_Init(n, __VA_ARGS__); for(int w=0; w<n; ++w){MACRO_VEC_ROW_Scan(w, __VA_ARGS__);}
template<typename T> void MACRO_VEC_ROW_Init(int n, T& t) { t.resize(n); }
template<typename First, typename...Rest>void MACRO_VEC_ROW_Init(int n, First& first, Rest&...rest) { first.resize(n); MACRO_VEC_ROW_Init(n, rest...); }
template<typename T> void MACRO_VEC_ROW_Scan(int p, T& t) { std::cin >> t[p]; }
template<typename First, typename...Rest>void MACRO_VEC_ROW_Scan(int p, First& first, Rest&...rest) { std::cin >> first[p]; MACRO_VEC_ROW_Scan(p, rest...); }
#define VEC(type, c, n) std::vector<type> c(n);for(auto& i:c)std::cin>>i;
#define MAT(type, c, m, n) std::vector<std::vector<type>> c(m, std::vector<type>(n));for(auto& R:c)for(auto& w:R)std::cin>>w;
// output
#define OUT(dist) std::cout<<(dist);
#define FOUT(n, dist) std::cout<<std::fixed<<std::setprecision(n)<<(dist);
#define SOUT(n, c, dist) std::cout<<std::setw(n)<<std::setfill(c)<<(dist);
#define SP std::cout<<" ";
#define TAB std::cout<<"\t";
#define BR std::cout<<"\n";
#define SPBR(w, n) std::cout<<(w + 1 == n ? '\n' : ' ');
#define ENDL std::cout<<std::endl;
#define FLUSH std::cout<<std::flush;
#define SHOW(dist) {std::cerr << #dist << "\t:" << (dist) << "\n";}
#define SHOWVECTOR(v) {std::cerr << #v << "\t:";for(const auto& xxx : v){std::cerr << xxx << " ";}std::cerr << "\n";}
#define SHOWVECTOR2(v) {std::cerr << #v << "\t:\n";for(const auto& xxx : v){for(const auto& yyy : xxx){std::cerr << yyy << " ";}std::cerr << "\n";}}
#define SHOWQUEUE(a) {auto tmp(a);std::cerr << #a << "\t:";while(!tmp.empty()){std::cerr << tmp.front() << " ";tmp.pop();}std::cerr << "\n";}
// utility
#define ALL(a) (a).begin(),(a).end()
#define FOR(w, a, n) for(int w=(a);w<(n);++w)
#define RFOR(w, a, n) for(int w=(n)-1;w>=(a);--w)
#define REP(w, n) for(int w=0;w<int(n);++w)
#define RREP(w, n) for(int w=int(n)-1;w>=0;--w)
#define FORLL(w, a, n) for(ll w=ll(a);w<ll(n);++w)
#define RFORLL(w, a, n) for(ll w=ll(n)-1;w>=ll(a);--w)
#define REPLL(w, n) for(ll w=0;w<ll(n);++w)
#define RREPLL(w, n) for(ll w=ll(n)-1;w>=0;--w)
#define IN(a, x, b) (a<=x && x<b)
template<class T> inline T CHMAX(T& a, const T b) { return a = (a < b) ? b : a; }
template<class T> inline T CHMIN(T& a, const T b) { return a = (a > b) ? b : a; }
#define EXCEPTION(msg) throw std::string("Exception : " msg " [ in ") + __func__ + " : " + std::to_string(__LINE__) + " lines ]"
#define TRY(cond, msg) try {if (cond) EXCEPTION(msg);}catch (std::string s) {std::cerr << s << std::endl;}
//void CHECKTIME(std::function<void()> f) { auto start = std::chrono::system_clock::now(); f(); auto end = std::chrono::system_clock::now(); auto res = std::chrono::duration_cast<std::chrono::nanoseconds>((end - start)).count(); std::cerr << "[Time:" << res << "ns  (" << res / (1.0e9) << "s)]\n"; }
// test
template<class T> std::vector<std::vector<T>> VV(int n, int m, T init = T()) {
	return std::vector<std::vector<T>>(n, std::vector<T>(m, init));
}
template<typename S, typename T>
std::ostream& operator<<(std::ostream& os, std::pair<S, T> p) {
	os << "(" << p.first << ", " << p.second << ")"; return os;
}

// type/const
#define int ll
using ll = long long;
using ull = unsigned long long;
using ld = long double;
using PAIR = std::pair<int, int>;
using PAIRLL = std::pair<ll, ll>;
constexpr int INFINT = 1 << 30;                          // 1.07x10^ 9
constexpr int INFINT_LIM = (1LL << 31) - 1;              // 2.15x10^ 9
constexpr ll INFLL = 1LL << 60;                          // 1.15x10^18
constexpr ll INFLL_LIM = (1LL << 62) - 1 + (1LL << 62);  // 9.22x10^18
constexpr double EPS = 1e-10;
constexpr int MOD = 1000000007;
constexpr double PI = 3.141592653589793238462643383279;
template<class T, size_t N> void FILL(T(&a)[N], const T& val) { for (auto& x : a) x = val; }
template<class ARY, size_t N, size_t M, class T> void FILL(ARY(&a)[N][M], const T& val) { for (auto& b : a) FILL(b, val); }
template<class T> void FILL(std::vector<T>& a, const T& val) { for (auto& x : a) x = val; }
template<class ARY, class T> void FILL(std::vector<std::vector<ARY>>& a, const T& val) { for (auto& b : a) FILL(b, val); }
// ------------>8------------------------------------->8------------

ll powMod(ll n, ll p, ll mod) {
	ll res = 1;
	while (p) {
		if (p & 1) (res *= n) %= mod;
		(n *= n) %= mod;
		p >>= 1;
	}
	return res;
}
ll invMod(ll n, ll mod) {
	return powMod(n, MOD - 2, MOD);
}

const signed FACT_MAX_N = 1000006;
signed fact[FACT_MAX_N];
signed factInv[FACT_MAX_N];
struct INIT_FACT {
	INIT_FACT() {
		fact[0] = 1;
		for (int i = 1; i < FACT_MAX_N; ++i) fact[i] = (long long)i * fact[i - 1] % MOD;
		factInv[FACT_MAX_N - 1] = powMod(fact[FACT_MAX_N - 1], MOD - 2, MOD);
		for (int i = FACT_MAX_N - 2; i >= 0; --i) factInv[i] = (long long)(i + 1) * factInv[i + 1] % MOD;
	}
} init_fact;

/* n,r<=10^6, query O(1)*/
ll Permutation(int n, int r) {
	if (r == 0) return 1;
	if (n < r) return 0;
	return (long long)fact[n] * factInv[n - r] % MOD;
}
ll Combination(int n, int r) {
	if (r == 0) return 1;
	if (n < r) return 0;
	return (long long)fact[n] * factInv[n - r] % MOD * factInv[r] % MOD;
}

int dp[6003][3003];

signed main() {
	INIT;

	VAR(int, n, m);
	VAR(std::string, s);
	VEC_ROW(int, m, l, r);
	REP(i, m) --l[i];

	std::stack<PAIR> st;
	REP(i, m) {
		if (!st.empty()){
			if (r[i] <= st.top().second) continue;
			if (st.top().first == l[i] && st.top().second <= r[i]) {
				st.pop();
				--i;
				continue;
			}
		}
		st.push(PAIR(l[i], r[i]));
	}

	std::vector<std::vector<PAIR>> lr;
	int pre = -1;
	{
		std::vector<PAIR> pv;
		while (!st.empty()) {
			PAIR p = st.top(); st.pop();
			pv.emplace_back(p);
		}
		std::reverse(ALL(pv));

		for (const auto& p : pv) {
			if (pre < p.first) {
				lr.emplace_back();
			}
			lr.back().emplace_back(p);
			pre = p.second;
		}
	}

	int ans = 1;
	int pos = 0;
	for (auto& v : lr) {
		dp[pos][0] = 1;

		int L = v.front().first, R = v.front().first;
		int t = v.back().second;
		int sz = 0;
		int preR = INFINT;
		v.emplace_back(t, t);
		for (const auto& p : v) {
			int add = 0, del = 0;
			while (R < p.second) {
				add += s[R] == '1';
				++R;
			}
			while (L < p.first) {
				++del;
				++L;
			}

			REP(i, del + 1) FOR(j, i, sz + 1) {
				if (dp[pos][j] == 0) continue;
				if (j - i > preR - p.first) continue;
				(dp[pos + 1][j - i + add] += Combination(del, i) * dp[pos][j]) %= MOD;
			}
			sz = p.second - p.first;
			preR = p.second;
			++pos;
		}
		(ans *= dp[pos][0]) %= MOD;
		++pos;
	}
	OUT(ans)BR;
	return 0;
}
/*
|-------|
   |--------|
---      ----
del       add
*/

Measured memory_bytes: 40832