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#include <stdbool.h>
#include <stdio.h>
#include <string.h>
#define N 1500
#define ischar(c) (c >= 'a' && c <= 'z')
typedef struct { int nout, out[N]; char s[4], outc[N][4]; } node_t;
bool visited[N];
char *buf, line[N][N];
int n, nother, c[N][N], f[N][N];
node_t m[N];
int findm(char *s) {
for (int k = 0; k < n; k++)
if (m[k].s[0] == s[0] && m[k].s[1] == s[1] && m[k].s[2] == s[2])
return k;
return n;
}
void resetfc(void) {
for (int i = 0; i < n; i++)
for (int j = 0; j < m[i].nout; j++)
c[i][m[i].out[j]] = 1;
for (int i = 0; i < n; i++)
memset(f[i], 0, N * sizeof(int));
}
bool dfs(int v, int t) {
if (v == t) return true;
if (visited[v]) return false;
visited[v] = true;
for (int i = 0; i < m[v].nout; i++) {
int u = m[v].out[i];
if (c[v][u] == 0) continue;
c[v][u]--;
c[u][v]++;
f[v][u]++;
if (dfs(u, t)) return true;
c[v][u]++;
c[u][v]--;
f[v][u]--;
}
return false;
}
bool residualpath(int s, int t) {
memset(visited, 0, N * sizeof(bool));
return dfs(s, t);
}
/* Ford-Fulkerson */
bool flowatmost(int s, int t, int k) {
int flow;
resetfc();
for (flow = 0; flow <= k && residualpath(s, t); flow++) ;
return flow <= k;
}
int main() {
for (n = 0; (buf = fgets(line[n], N, stdin)) != NULL; n++) {
for (int i = 0; ischar(*buf); m[n].s[i++] = *(buf++)) ;
for (int i = 0; *buf != '\n'; i++) {
while (!ischar(*buf)) buf++;
for (int j = 0; ischar(*buf); m[n].outc[i][j++] = *(buf++)) ;
}
}
for (int i = 0; i < n; i++) {
for (int j = 0; m[i].outc[j][0]; j++) {
int k = findm(m[i].outc[j]);
m[i].out[m[i].nout++] = k;
m[k].out[m[k].nout++] = i;
if (k == n) {
for (int k = 0; m[i].outc[j][k]; k++)
m[n].s[k] = m[i].outc[j][k];
n++;
}
}
}
for (int t = 1; t < n; t++)
if (flowatmost(0, t, 3)) nother++;
printf("%d\n", nother * (n-nother));
return 0;
}
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