#pragma GCC optimize("Ofast")
#pragma GCC target("avx2")

#define rd_skip() while(*rp++>=48)
#define rd() ({long _v=0,_c;while(_c=*rp++-48,_c>=0)_v=_v*10+_c;_v;})

char t[500004];

long f(char*s){
	while(*s){
		char*u=t;
		while(*(long*)s==*(long*)u){
			s+=sizeof(long);
			u+=sizeof(long);
		}
		while(*s==*u){
			++s;
			++u;
		}
		++u;
		while(*(long*)s==*(long*)u){
			s+=sizeof(long);
			u+=sizeof(long);
		}
		while(*s==*u){
			++s;
			++u;
		}
		if(*s++!=10){
			return 0;
		}
	}
	return 1;
}

int main(){
	char*mmap();
	char*rp=mmap(0l,1l<<25,1,2,0,0ll);
	rd_skip();
	long m=rd();
	if(rp[m*2+2]){
		// case: n != 2
		long j=0;
		char*s1=rp;
		char*s2=rp+(m+1);
		long v;
		while(v=*(long*)(s1+j),v==*(long*)(s2+j)){
			*(long*)(t+j)=v;
			j+=sizeof(long);
		}
		while(s1[j]==s2[j]){
			t[j]=s1[j];
			++j;
		}
		long r=48;
		t[j]=s1[j];
		memcpy(t+(j+1),s2+j,m-j);
		r+=f(rp);
		t[j]=s2[j];
		memcpy(t+(j+1),s1+j,m-j);
		r+=f(rp);
		write(1,&r,1);
	}
	else{
		// case: n == 2
		long j=0,k=m-1;
		char*s1=rp;
		char*s2=rp+(m+1);
		while(*(long*)(s1+j)==*(long*)(s2+j)){
			j+=sizeof(long);
		}
		while(s1[j]==s2[j]){
			++j;
		}
		if(m>=sizeof(long)){
			while(*(long*)(s1+(k-(sizeof(long)-1)))==*(long*)(s2+(k-(sizeof(long)-1)))){
				k-=sizeof(long);
			}
		}
		while(s1[k]==s2[k]){
			--k;
		}
		long r;
		if(j==k){
			r='2';
		}
		else{
			r=48;
			r+=memcmp(s1+j,s2+(j+1),k-j)==0;
			r+=memcmp(s1+(j+1),s2+j,k-j)==0;
		}
		write(1,&r,1);
	}
	_exit(0);
}