Problem:
Problem D. Prefix Suffix Search

As an English learner, sometimes you cannot remember the entire spelling of English words perfectly, but you can only remember their prefixes and suffixes. For example, you may want to use a word which begins with 'appr' and ends with 'iate', but forget the middle part of the word. It may be 'appreciate', 'appropriate', or something like them.

By using an ordinary dictionary, you can look up words beginning with a certain prefix, but it is inconvenient for further filtering words ending with a certain suffix. Thus it is helpful to achieve dictionary functionality which can be used for finding words with a given prefix and suffix. In the beginning, let's count the number of such words instead of explicitly listing them.

More formally, you are given a list of $N$ words. Next, you are given $Q$ queries consisting of two strings. Your task is to write a program which outputs the number of words with the prefix and suffix for each query in the given list.

Input

The input consists of a single test case in the following format.

$N$ $Q$
$w_1$
$...$
$w_N$
$p_1$ $s_1$
$...$
$p_Q$ $s_Q$

The first line contains two integers $N$ and $Q$, where $N$ ($1 \leq N \leq 10^5$) is the number of words in the list, and $Q$ ($1 \leq Q \leq 10^5$) is the number of queries. The $i$-th line of the following $N$ lines contains a string $w_i$. The $i$-th of the following $Q$ lines contains two strings $p_i$ and $s_i$, which are a prefix and suffix of words to be searched, respectively.

You can assume the followings:

All the strings in an input are non-empty and consist only of lowercase English letters.

The total length of input strings does not exceed $2,500,000$.

Words in the given list are unique: $w_i \ne w_j$ if $i \ne j$.

Pairs of a prefix and suffix are unique: $(p_i, s_i) \ne (p_j, s_j)$ if $i \ne j$.

Output

For each query, output the number of words with a given prefix and suffix in the given list per a line.

Examples

Sample Input 1

6 7
appreciate
appropriate
acceptance
ace
acm
acetylene
appr iate
a e
a a
ac ce
ace e
acceptance acceptance
no match

Output for Sample Input 1

2
5
0
2
2
1
0

Sample Input 2

5 5
d
dd
ddd
dddd
ddddd
d d
dd dd
ddd ddd
d dddd
ddddd dd

Output for Sample Input 2

5
4
3
2
1

Sample Input 3

7 4
connected
disconnected
graph
directed
diameter
distance
minor
c ed
di ed
dis ed
dis e

Output for Sample Input 3

1
2
1
1

Solution in C++11 (judge verdict: Accepted)

    #include <bits/stdc++.h>

                                            //    #include <boost/multiprecision/cpp_int.hpp>
 
                               	       #define int long long
                                                #define inf  1000000007
                                              #define pa pair<int,int>
                                               #define pad pair<double,double>
                                                #define ll long long
                                                #define pal pair<double,double>
                                                #define ppap pair<pa,int>
                                          #define PI 3.14159265358979323846
                                                #define paa pair<pa,pa>
                                                #define  mp make_pair
                                                #define  pb push_back
                                                #define EPS (1e-10)
                                                #define equals(a,b) (fabs((a)-(b))<EPS)
                                            //    #define double long double
        int dx[4]={0,-1,0,1};
        int dy[4]={1,0,-1,0};
                                                using namespace std;
                                       			class pa3{
                                                	public:
                                                	int x,y,z;
                                                	pa3(int x=0,int y=0,int z=0):x(x),y(y),z(z) {}
                                                	bool operator < (const pa3 &p) const{
                                                		if(x!=p.x) return x<p.x;
                                                		if(y!=p.y) return y<p.y;
                                                		 return z<p.z;
                                                		//return x != p.x ? x<p.x: y<p.y;
                                                	}
                                       				bool operator > (const pa3 &p) const{
                                                		if(x!=p.x) return x>p.x;
                                                		if(y!=p.y) return y>p.y;
                                                		 return z>p.z;
                                                		//return x != p.x ? x<p.x: y<p.y;
                                                	}
                                                	bool operator == (const pa3 &p) const{
                                                		return x==p.x && y==p.y && z==p.z;
                                                	}
                                                		bool operator != (const pa3 &p) const{
                                                			return !( x==p.x && y==p.y && z==p.z);
                                                	}
                                                
                                                };
                                                
                                                class pa4{
                                                	public:
                                                	int x;
                                                	int y,z,w;
                                                	pa4(int x=0,int y=0,int z=0,int w=0):x(x),y(y),z(z),w(w) {}
                                                	bool operator < (const pa4 &p) const{
                                                		if(x!=p.x) return x<p.x;
                                                		if(y!=p.y) return y<p.y;
                                                		if(z!=p.z)return z<p.z;
                                                		return w<p.w;
                                                		//return x != p.x ? x<p.x: y<p.y;
                                                	}
                                                	bool operator > (const pa4 &p) const{
                                                		if(x!=p.x) return x>p.x;
                                                		if(y!=p.y) return y>p.y;
                                                		if(z!=p.z)return z>p.z;
                                                		return w>p.w;
                                                		//return x != p.x ? x<p.x: y<p.y;
                                                	}
                                                	bool operator == (const pa4 &p) const{
                                                		return x==p.x && y==p.y && z==p.z &&w==p.w;
                                                	}
                                                	
                                                	bool operator != (const pa4 &p) const{
                                                		return !(x==p.x && y==p.y && z==p.z &&w==p.w);
                                                	}
                                                		
                                                
                                                };
                                                class pa2{
                                                	public:
                                                	int x,y;
                                                	pa2(int x=0,int y=0):x(x),y(y) {}
                                                	pa2 operator + (pa2 p) {return pa2(x+p.x,y+p.y);}
                                                	pa2 operator - (pa2 p) {return pa2(x-p.x,y-p.y);}
                                                	bool operator < (const pa2 &p) const{
                                                		return x!= p.x ? x<p.x: y<p.y;
                                                	}
                                                	bool operator > (const pa2 &p) const{
                                                		return x != p.x ? x>p.x: y>p.y;
                                                	}
                                                	bool operator == (const pa2 &p) const{
                                                		return abs(x-p.x)==0 && abs(y-p.y)==0;
                                                	}
                                                	bool operator != (const pa2 &p) const{
                                                		return !(abs(x-p.x)==0 && abs(y-p.y)==0);
                                                	}
                                                		
                                                
                                                };
                                                
                                              
                                                
                                                       #define ppa pair<int,pas>
                                                class Point{
                                                	public:
                                                	double x,y;
                                                	Point(double x=0,double y=0):x(x),y(y) {}
                                                	Point operator + (Point p) {return Point(x+p.x,y+p.y);}
                                                	Point operator - (Point p) {return Point(x-p.x,y-p.y);}
                                                	Point operator * (double a) {return Point(x*a,y*a);}
                                                	Point operator / (double a) {return Point(x/a,y/a);}
                                                	double absv() {return sqrt(norm());}
                                                	double norm() {return x*x+y*y;}
                                                	bool operator < (const Point &p) const{
                                                		return x != p.x ? x<p.x: y<p.y;
                                                	}
                                                	bool operator == (const Point &p) const{
                                                		return fabs(x-p.x)<EPS && fabs(y-p.y)<EPS;
                                                	}
                                                };
                                                typedef Point Vector;
                                         #define pl pair<int,pas>
                                                struct Segment{
                                                Point p1,p2;
                                                };
                                                 double dot(Vector a,Vector b){
                                                	return a.x*b.x+a.y*b.y;
                                                }
                                                double cross(Vector a,Vector b){
                                                	return a.x*b.y-a.y*b.x;
                                                }
                                            
                    bool parareru(Point a,Point b,Point c,Point d){
                    //	if(abs(cross(a-b,d-c))<EPS)cout<<"dd "<<cross(a-b,d-c)<<endl;
                    	return abs(cross(a-b,d-c))<EPS;
                    }
                    double distance_ls_p(Point a, Point b, Point c) {
                      if ( dot(b-a, c-a) < EPS ) return (c-a).absv();
                      if ( dot(a-b, c-b) < EPS ) return (c-b).absv();
                      return abs(cross(b-a, c-a)) / (b-a).absv();
                    }
                    bool is_intersected_ls(Segment a,Segment b) {
                    	if(a.p1==b.p1||a.p2==b.p1||a.p1==b.p2||a.p2==b.p2) return 1;
                    	if(parareru((a.p2),(a.p1),(a.p1),(b.p2))&&parareru((a.p2),(a.p1),(a.p1),(b.p1))){
                    //		cout<<"sss"<<endl;
                    		if(dot(a.p1-b.p1,a.p1-b.p2)<EPS) return true;
                    		if(dot(a.p2-b.p1,a.p2-b.p2)<EPS) return true;
                    		if(dot(a.p1-b.p1,a.p2-b.p1)<EPS) return true;
                    		if(dot(a.p1-b.p2,a.p2-b.p2)<EPS) return true;
                    		return false;
                    	}
                      else return ( cross(a.p2-a.p1, b.p1-a.p1) * cross(a.p2-a.p1, b.p2-a.p1) < EPS ) && ( cross(b.p2-b.p1, a.p1-b.p1) * cross(b.p2-b.p1, a.p2-b.p1) < EPS );
                    }
                     
                    double segment_dis(Segment a,Segment b){
                    	if(is_intersected_ls(a,b))return 0;
                    	double r=distance_ls_p(a.p1, a.p2, b.p1);
                    	r=min(r,distance_ls_p(a.p1, a.p2, b.p2));
                    	r=min(r,distance_ls_p(b.p1, b.p2, a.p2));
                    	r=min(r,distance_ls_p(b.p1, b.p2, a.p1));
                    	return r;
                    }
                    Point intersection_ls(Segment a, Segment b) {
                      Point ba = b.p2-b.p1;
                      double d1 = abs(cross(ba, a.p1-b.p1));
                      double d2 = abs(cross(ba, a.p2-b.p1));
                      double t = d1 / (d1 + d2);
                     
                      return a.p1 + (a.p2-a.p1) * t;
                    }
                     
                                    string itos( int i ) {
                                    ostringstream s ;
                                    s << i ;
                                    return s.str() ;
                                    }
                                     
                                    int gcd(int v,int b){
                                    	if(v==0) return b;
                                    	if(v>b) return gcd(b,v);
                                    	if(v==b) return b;
                                    	if(b%v==0) return v;
                                    	return gcd(v,b%v);
                                    }
                     
                                    double distans(double x1,double y1,double x2,double y2){
                                    	double rr=(x1-x2)*(x1-x2)+(y1-y2)*(y1-y2);
                                    	return sqrt(rr);
                                    	
                                    }
                                                        /*
        double bekid(double w,int r){
        	if(r==0) return 1.0;
        	if(r==1) return w;
        	if(r%2) return bekid(w,r-1)*w;
        	double f=bekid(w,r/2);
        	return f*f;
        }*/
                                    int mod;
                    int beki(int wa,int rr,int warukazu){
                    	if(rr==0) return 1%warukazu;
                    	if(rr==1) return wa%warukazu;
                    	if(rr%2==1) return (beki(wa,rr-1,warukazu)*wa)%warukazu;
                    	int zx=beki(wa,rr/2,warukazu);
                    	return (zx*zx)%warukazu;
                    }
                          /*          
                    int pr[401000];
                    int inv[401000];
                   
                   

                  
        			int comb(int nn,int rr){
        				int r=pr[nn]*inv[rr];
        				r%=mod;
        				r*=inv[nn-rr];
        				r%=mod;
        				
        				return r;
        			}
                  
                    void gya(int ert){
                    	pr[0]=1;
                    	for(int i=1;i<ert;i++){
                    		pr[i]=(pr[i-1]*i)%mod;
                    	}
                    	for(int i=0;i<ert;i++) inv[i]=beki(pr[i],mod-2,mod);
                    	
                    }
                    */
                    
                  //   cin.tie(0);
        		//	ios::sync_with_stdio(false);
        			//priority_queue<pa3,vector<pa3>,greater<pa3>> pq;            
                     //sort(ve.begin(),ve.end(),greater<int>());



struct segsum{
	//       1
	//   2        3
	// 4   5   6    7
	
	
	private:
	public:
	
	// 1<<10 = 1024
	// 1<<11 = 2048
	// 1<<12 = 4096
	// 1<<13 = 8192
	// 1<<14 = 16384
	// 1<<15 = 32768
	// 1<<16 = 65536
	// 1<<17 = 131072
	// 1<<18 = 262144
	
	int cor=(1<<17);
	
	vector<int> vec;
	vector<int> lazy;
	
	void shoki1(){
		vec.resize(2*cor+3, 0);
	}
		void shoki2(){
			for(int i=cor-1;i>0;i--) vec[i]=vec[2*i]+vec[2*i+1];
		}
			void clear(){
		    
	    	for(int i=0;i<(int)vec.size();i++)vec[i]=0;
    	}
	void updadd(int x,int w){
		//x 項目に w加算
		x+=cor;
		vec[x]+=w;
		while(1){
			x/=2;
			if(x==0) break;
			vec[x]=vec[2*x]+vec[2*x+1];
		}
		
	}
	
	void updchan(int x,int w){
		//x項目をwに変更
		x+=cor;
		vec[x]=w;
		while(1){
			x/=2;
			if(x==0) break;
			vec[x]=vec[2*x]+vec[2*x+1];
		}
		
	}
	// [a,b)
	// k-th node
	// k no kukanha [l,r)
	int sum(int a,int b,int k=1,int l=0,int r=-10){
		if(r<0)r=cor;
		
	//	cout<<a<<" "<<b<<" "<<k<<" "<<l<<" "<<r<<endl;
		
		if(a<=l && r<=b){
			return vec[k];
		}
		if(r<=a || b<=l){
			return 0;
		}
		
		int v1=sum(a,b,k*2,l,(l+r)/2),v2=sum(a,b,k*2+1,(l+r)/2,r);
		return v1+v2;
	}
	
};
segsum ss;

int high1[100020];
int high2[100020];
vector<pair<string,int>> ve1,ve2;
int a[100020];
int ans[100020]={0};
int aa[100020];
vector<pa3> ve[100020];
int gya[100020];
  signed main(){
 	              cin.tie(0);
   		ios::sync_with_stdio(false);
int n,q;
  	cin>>n>>q;
  	ss.shoki1();
  	ss.shoki2();
  	ve1.pb(mp("A",0));
  	ve2.pb(mp("A",0));
  	for(int i=0;i<n;i++){
  		string s;
  		cin>>s;
  		ve1.pb(mp(s,i));
  		reverse(s.begin(),s.end());
  		ve2.pb(mp(s,i));
  	}
  	sort(ve1.begin(),ve1.end());
  	
  	sort(ve2.begin(),ve2.end());
  	
  	for(int i=1;i<=n;i++)high1[ve1[i].second]=i;
  	for(int i=1;i<=n;i++)high2[ve2[i].second]=i;
  	for(int i=0;i<n;i++){
  		a[high1[i]]=high2[i];
  	}
  	a[0]=0;
  	aa[0]=0;
  	
  
  	for(int i=0;i<n;i++){
  		aa[high1[i]]=high2[i];
  	}
  	for(int i=0;i<=n;i++)gya[aa[i]]=i;
  //		for(int i=0;i<=n;i++)cout<<i<<"  "<<aa[i]<<endl;
  	for(int ii=0;ii<q;ii++){
  		string p,s;
  		cin>>p>>s;
  		reverse(s.begin(),s.end());
  		pair<string ,int> t1=mp(p,-100);
  		int x1=lower_bound(ve1.begin(),ve1.end(),t1)-ve1.begin();
  		t1.first+="~";
  		int x2=lower_bound(ve1.begin(),ve1.end(),t1)-ve1.begin();
 		
  		t1=mp(s,-100);
  		int y1=lower_bound(ve2.begin(),ve2.end(),t1)-ve2.begin();
  		t1.first+="~";
  		int y2=lower_bound(ve2.begin(),ve2.end(),t1)-ve2.begin();
 		
  	//	cout<<x1<<" "<<x2<<" "<<y1<<" "<<y2<<endl;
  		if(x1==x2 || y1==y2 ) continue;
  		x1--;
  		x2--;
  		y1--;
  		y2--;
  		
  			ve[y1].pb((pa3){x1,ii,1});
  			ve[y1].pb((pa3){x2,ii,-1});  		
  			ve[y2].pb((pa3){x1,ii,-1});
  			ve[y2].pb((pa3){x2,ii,1});
  		
  	}
  	
  	for(int i=0;i<=n;i++){
  		ss.updadd(gya[i],1);
  	//	for(int j=0;j<=n;j++)cout<<ss.vec[ss.cor+j]<<" ";
  	//	cout<<endl;
  		for(auto v:ve[i]){
  			ans[v.y]+=v.z*(ss.sum(0,v.x+1));
  		}
  	}
  	
  	for(int i=0;i<q;i++)cout<<ans[i]<<endl;

  	return 0;
  	
               }