#include<iostream>
#include<cstdio>
#include<string.h>
#include<cstring>
using namespace std;
const int MOD = 1000000007;
int n,d[1010][1010],q,flag,x,y,z;
char s[1010];
inline int read()
{
    int x=0,f=1;char ch=getchar();
    while(ch<'0'||ch>'9'){if(ch=='-')f=-1;ch=getchar();}
    while(ch>='0'&&ch<='9'){x=x*10+ch-'0';ch=getchar();}
    return x*f;
}
int main()
{
	n=read(),q=read();
    scanf("%s",s+1);
    if (n<=500&&q<=500)
    {
		while (q--)
		{
			flag=read();
			if (flag==1)
			{
				x=read()+1,y=read()+1,z=read();
				for (int i=x;i<=y;i++)
					s[i]=(s[i]-'a'+z)%26+'a';
			}
			else
			{
				x=read()+1,y=read()+1; 
				memset(d,0,sizeof(d));
			    for(int i=x;i<=y;i++) d[i][i]=1;
			    for(int i=1;i<y-x+1;i++)
			    {
			        for(int j=x;j<=y-i;j++)
			        {
			            if(s[j]==s[j+i])
			                d[j][i+j]=(d[j][i+j-1]+d[j+1][i+j]+1)%MOD;
			            else
			                d[j][i+j]=(d[j][i+j-1]+d[j+1][i+j]-d[j+1][i+j-1]+MOD)%MOD;
			        }
			    }
			    printf("%d\n",d[x][y]%MOD);
			}
		}
	}
	else
	{
		for(int i=1;i<=n;i++) d[i][i]=1;
	    for(int i=1;i<n;i++)
	    {
	        for(int j=x;j<=n-i;j++)
	        {
	            if(s[j]==s[j+i])
	                d[j][i+j]=(d[j][i+j-1]+d[j+1][i+j]+1)%MOD;
	            else
	                d[j][i+j]=(d[j][i+j-1]+d[j+1][i+j]-d[j+1][i+j-1]+MOD)%MOD;
	        }
	    }
	    while (q--)
		{
			flag=read(),x=read(),y=read();
			printf("%d\n",d[x][y]);
		}
	}
    return 0;
}