#include <map>
#include <iostream>
#include<bits/stdc++.h>
using namespace std;
#define test int t;scanf("%d", &t);while(t--)
#define sd(n) scanf("%d", &n)
#define loop(i, n) for(int i = 0;i<n;i++)
#define kloop(i, k, n) for(int i=k;i<n;i++)
#define rloop(i, n) for(int i = n;i>=0;i--)
#define rkloop(i, n, k) for(int i = n;i>=k;i--)
#define MOD 1000000007
#define PI 3.1415926535897932384626433832795
#define interactive(x) cout<<x<<"\n";fflush(stdout)
#define fil(name, val) memset(name, val, sizeof(name))
#define pb push_back
#define ll long long
/*int fact[MAXN];
int invfact[MAXN];
int inv(int a, int b){
    if(b==0)
        return 1;
    if(b&1)
        return (long long)a*inv(a, b-1)%MOD;
    else{
        int res = inv(a, b>>1);
        return (long long)res*res%MOD;
    }
}
void init(){
    fact[0] = 1;
    for(int i=1;i<MAXN;i++){
        fact[i] = (long long)fact[i-1]*i%MOD;
    }
    invfact[MAXN-1] = inv(fact[MAXN-1], MOD-2);
    for(int i=MAXN-1;i>0;i--){
        invfact[i-1] = (long long)invfact[i]*i%MOD;
    }
}
int C(int n, int r){
    if(r>n || r<0)
        return 0;
    return (long long)((long long)fact[n]*invfact[r]%MOD)*invfact[n-r]%MOD;
}*/
int n, q, type, l, r, t;
char arr[100005];
string s = "";
int go(int i, int j){
    /*cout<<i<<" "<<j<<"\n";*/
    if(i==j)    return 1;
    if(j-i==1)  return 2+(s[i]==s[i+1]);
    if(j<i) return 0;
    return (go(i+1, j)+go(i, j-1)-go(i+1, j-1)+(s[i]==s[j])*(go(i+1, j-1)+1))%MOD;
}
void solve(){
    string alph = "abcdefghijklmnopqrstuvwxyz";
    sd(n);
    sd(q);
    loop(i, n)  cin>>arr[i];
    for(int Q=0;Q<q;Q++){
        sd(type);
        if(type==1){
            sd(l);
            sd(r);
            sd(t);
            for(int L=l;L<=r;L++){
                arr[L] = alph[((arr[L]-'a'+t)%26)];
            }
        }
        else{
            s = "";
            sd(l);
            sd(r);
            for(int L=l;L<=r;L++){
                s+=arr[L];
            }
            /*cout<<s<<"\n";*/
            int ans = go(0, s.length()-1);
            cout<<ans%MOD<<"\n";
        }
    }
}
int main(){
    /*FILE *fin = freopen("C-small-attempt0.in", "r", stdin);
	assert( fin!=NULL );
	FILE *fout = freopen("C-small.out", "w", stdout);*/
    solve();
    return 0;
}