[ctsc2014]企鹅qq

using namespace std;
int l,m,n,ans,now;
char s[202];
unsigned long long t[30003];
unsigned long long _hash[30003][202];
unsigned long long hash_[30003][202];
int ()
{
    scanf("%d%d%d",&n,&l,&m);
    for(register int i=1;i<=n;++i)
    {
        scanf("%s",s+1);
        for(register int j=1;j<=l;++j) _hash[i][j]=_hash[i][j-1]*223+s[j];
        for(register int j=l;j>=1;--j) hash_[i][j]=hash_[i][j+1]*233+s[j];
    }
    for(register int i=1;i<=l;++i)
    {
        for(register int j=1;j<=n;++j) t[j]=_hash[j][i-1]*229+hash_[j][i+1]*239;
        sort(t+1,t+n+1);now=1;
        for(register int j=2;j<=n;++j) t[j-1]==t[j]?ans+=now++:now=1;
    }
    printf("%dn",ans);
    return 0;
}