#include<bits/stdc++.h>
using namespace std;
struct p{
    char x;
    char y;
};
p a[1000010];
int main(){
    //freopen("poker.in","r",stdin);
    //freopen("poker.out","w",stdout);
    int n;
    cin>>n;

    for(int i=0;i<n;i++){
        cin>>a[i].x;
        cin>>a[i].y;
        if(a[i].y==1){
            a[i].y='1';
        } 
        else if(a[i].y==2){
            a[i].y=='2';
        }
        else if(a[i].y==3){
            a[i].y=='3';
        }
        else if(a[i].y==4){
            a[i].y=='4';
        }
        else if(a[i].y==5){
            a[i].y=='5';
        }
        else if(a[i].y==6){
            a[i].y=='6';
        }
        else if(a[i].y==7){
            a[i].y=='7';
        }
        else if(a[i].y==8){
            a[i].y=='8';
        }
        else if(a[i].y==9){
            a[i].y=='9';
        }
        else if(a[i].y=='A'){
            a[i].y=='A';
        }
        else if(a[i].y=='T'){
            a[i].y=='T';
        }
        else if(a[i].y=='J'){
            a[i].y=='J';
        }
        else if(a[i].y=='Q'){
            a[i].y=='Q';
        }
        else if(a[i].y=='K'){
            a[i].y=='K';
        }
        else continue;
    }
    int cnt=0;
    char Q,W,E,R,T,Y,U,I,O,P,A,S,D,F,G,H,J,K,L,Z,X,C,V,B; 
    char Q1,W1,E1,R1,T1,Y1,U1,I1,O1,P1,A1,S1,D1,F1,G1,H1,J1,K1,L1,Z1,X1,C1,V1,B1; 
    /*for(int i=0;i<n;i++){
        for(int j=0;j<n;j++){

            Q=a[i].x;
            Q1=a[i].y;
            
                W=a[j].x;
                W1=a[j].y;
                if(Q==W&&Q1==W1) continue;
                else if(Q!=W||Q1!=W1) cnt++;
            }
        }
    */
    int ans=0;
    char w,e,r,t;
    for(int i=0;i<n;i++){
        
        if(i+1<=n){
            w=a[i].x;
            e=a[i].y;
            r=a[i+1].x;
            t=a[i+1].y;
            if(w==r&&e==t){
                continue;
            }
            else if(w!=r||e!=t){
                ans++;
            }
        }
        else if(i+1>n){
            for(int i=n+1;i>=1;i--){
                if(i==n){
                    w=a[i].x;
                    e=a[i].y;
                    r=a[i-1].x;
                    t=a[i-1].y;
                    if(w==r&&e==t){
                        continue;
                    }
                    else if(w!=r||e!=t){
                        ans++;
                    }
                }
                else continue;
            }
        }
    }
    if(ans==1){
        cout<<51<<endl;
    }
    cout<<52-ans<<endl;
    return 0;
}