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| #include<bits/stdc++.h>
#define ll long long
#define ull unsigned long long
#define maxn
#define put() putchar('\n')
#define Tp template<typename Ty>
#define Ts template<typename Ty,typename... Ar>
using namespace std;
void read(int &x){
int f=1;x=0;char c=getchar();
while (c<'0'||c>'9') {if (c=='-') f=-1;c=getchar();}
while (c>='0'&&c<='9') {x=x*10+c-'0';c=getchar();}
x*=f;
}
namespace Debug{
Tp void _debug(char* f,Ty t){cerr<<f<<'='<<t<<endl;}
Ts void _debug(char* f,Ty x,Ar... y){while(*f!=',') cerr<<*f++;cerr<<'='<<x<<",";_debug(f+1,y...);}
Tp ostream& operator<<(ostream& os,vector<Ty>& V){os<<"[";for(auto& vv:V) os<<vv<<",";os<<"]";return os;}
#define gdb(...) _debug((char*)#__VA_ARGS__,__VA_ARGS__)
}using namespace Debug;
#define fi first
#define se second
#define mk make_pair
const int mod=1e9+7;
int power(int x,int y=mod-2) {
int sum=1;
while (y) {
if (y&1) sum=sum*x%mod;
x=x*x%mod;y>>=1;
}
return sum;
}
int nums[4][4],to[4][4],e[4][4],id[105],cnt;
int n,ans;
bool dfs(int x) {
int flag=0,vis=0,i;
for (i=0;i<3;i++) if (e[x][i]) {
flag=1;e[x][i]--;
vis|=(dfs(i)==0);
e[x][i]++;
}
if (!flag) return 0;
else return vis;
}
signed main(void){
int i,j;string s;
read(n);
for (i=1;i<=n;i++) {
cin>>s;
int tmp1=s[0]-'a';if (!id[tmp1]) id[tmp1]=++cnt;
int tmp2=s[s.size()-1]-'a';if (!id[tmp2]) id[tmp2]=++cnt;
nums[id[tmp1]-1][id[tmp2]-1]++;
}
for (i=0;i<3;i++) for (j=0;j<3;j++) to[i][j]=nums[i][j];
for (i=0;i<3;i++) to[i][i]=(to[i][i]-1)%2+1;
for (i=0;i<3;i++) for (j=i+1;j<3;j++) {
int x=min(to[i][j],to[j][i]);
x=max(x-1,0);
to[i][j]-=x;
to[j][i]-=x;
}
for (i=0;i<3;i++) for (j=0;j<3;j++) gdb(i,j,to[i][j]);
for (i=0;i<3;i++) for (j=0;j<3;j++) {
memcpy(e,to,sizeof(e));int flag=0;
if (e[i][j]) e[i][j]--,flag=(dfs(j)==0);
else flag=dfs(i);
ans+=flag*nums[i][j];
}
printf("%d\n",ans);
return 0;
}
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