//#include <bits/stdc++.h>
#include "bits/stdc++.h"
using namespace std;
typedef long long ll;


#include "boost/multiprecision/cpp_int.hpp"
#include "boost/multiprecision/cpp_dec_float.hpp"
namespace mp = boost::multiprecision;
typedef mp::cpp_int LL;
typedef mp::number<mp::cpp_dec_float<1024>> DD;// 仮数部が1024ビットの浮動小数点数型(TLEしたら小さくする)


typedef long double dd;
#define i_7 (ll)(1E9+7)
//#define i_7 998244353
#define i_5 i_7-2
ll mod(ll a){
    ll c=a%i_7;
    if(c>=0)return c;
    return c+i_7;
}
typedef pair<ll,ll> l_l;
typedef pair<dd,dd> d_d;
ll inf=(ll)1E16;
#define rep(i,l,r) for(ll i=l;i<=r;i++)
#define pb push_back
ll max(ll a,ll b){if(a<b)return b;else return a;}
ll min(ll a,ll b){if(a>b)return b;else return a;}
void Max(ll &pos,ll val){pos=max(pos,val);}//Max(dp[n],dp[n-1]);
void Min(ll &pos,ll val){pos=min(pos,val);}
void Add(ll &pos,ll val){pos=mod(pos+val);}
dd EPS=1E-9;
#define fastio ios::sync_with_stdio(false); cin.tie(0); cout.tie(0);
#define fi first
#define se second
#define endl "\n"
#define SORT(v) sort(v.begin(),v.end())
#define ERASE(v) v.erase(unique(v.begin(),v.end()),v.end())
#define POSL(v,x) (lower_bound(v.begin(),v.end(),x)-v.begin())
#define POSU(v,x) (upper_bound(v.begin(),v.end(),x)-v.begin())
template<class T,class S>
inline bool chmax(T &a, S b) {
    if(a < b) {
        a = b;
        return true;
    }
    return false;
}
template<class T,class S>
inline bool chmin(T &a, S b) {
    if(a > b) {
        a = b;
        return true;
    }
    return false;
}

void mod_print(ll k){
    ll P=1000;
    rep(y,1,P){
        ll x=mod(y*k);
        if(x+P>=i_7){
            x-=i_7;
        }
        if(abs(x)<=P){
            cout<<x<<"/"<<y<<endl;
            return;
        }
    }
    cout<<"nun"<<endl;
}
#define all(c) c.begin(),c.end()
//////////////////////////

vector<l_l>convert(vector<l_l>v){
    vector<l_l>r;
    ll n=v.size();
    rep(i,0,n-1){
        if(i==n-1||v[i].fi!=v[i+1].fi)r.pb(v[i]);
        else if(v[i]>v[i+1])swap(v[i],v[i+1]);
    }
    n=r.size();
    vector<l_l>res;
    ll mx=-inf;
    rep(i,0,n-1){
        if(chmax(mx,r[i].se)){
            res.pb(r[i]);
        }
    }
    return res;
}

ll po(ll i,ll p){
    if(p==0)return 1;
    else{
        i=mod(i);
        if(p==1)return i;
        if(p%2==0)return po(mod(i*i),p/2);
        return mod(i*po(i,p-1));
    }
}
ll bunbo(ll n){
    return po(n,i_5);
}


#define N 2000004
ll kai[N];
ll kai2[N];
void calc(){
    kai[0]=1;
    kai2[0]=1;
    rep(i,1,N-1){
        kai[i]=mod(kai[i-1]*i);
    }
    kai2[N-1]=po(kai[N-1],i_5);
    for(ll i=N-2;i>=0;i--){
        kai2[i]=mod(kai2[i+1]*(i+1));
    }
}
ll comb(ll n,ll k){
    if(n<k)return 0;
    if(n==0)return 1;
    return mod(mod(kai[n]*kai2[n-k])*kai2[k]);
}


int main(){fastio
    calc();
    ll n,m;cin>>n>>m;
    string s;cin>>s;
    vector<l_l>v(m);
    rep(i,0,m-1){
        cin>>v[i].fi>>v[i].se;
        v[i].fi--;v[i].se--;
    }
    v=convert(v);
   // for(auto x:v)cout<<x.fi<<" "<<x.se<<endl;cout<<"***"<<endl;
    m=v.size();
    ll cnt[n+1];
    cnt[0]=0;
    rep(i,0,n-1){
        cnt[i+1]=cnt[i]+s[i]-'0';
    }
    ll dp[m+1][n+1];memset(dp,0,sizeof(dp));
    dp[0][0]=1;
    rep(i,0,m-1){
        ll ad=(i==0?cnt[v[i].se+1]-cnt[v[i].fi]:cnt[v[i].se+1]-max(cnt[v[i].fi],cnt[v[i-1].se+1]));
        ll sp=(i==m-1?v[i].se+1-v[i].fi:min(v[i+1].fi,v[i].se+1)-v[i].fi);
        rep(j,0,n){
            if(dp[i][j]==0)continue;
            rep(k,0,sp){
                ll nxj=j+ad-k;
                if(nxj<0||nxj>n)continue;
                Add(dp[i+1][nxj],dp[i][j]*comb(sp,k));
            }
        }
       // cout<<ad<<" "<<sp<<endl;
        if(i==m-1)break;
        ll mx=v[i].se-v[i+1].fi+1;
        chmax(mx,0);
        rep(j,mx+1,n)dp[i+1][j]=0;
    }
    /*
    rep(i,0,m){
        rep(j,0,n){
            cout<<dp[i][j]<<" ";
        }cout<<endl;
    }cout<<endl;*/
    
    cout<<mod(dp[m][0])<<endl;
    
    return 0;
}
/*
 11 3
 10010010010
 1 4
 5 7
 11 11
 */



Measured memory_bytes: 61184