#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, m, i, j, k, ara[27] = {0}, count = 0;
  char s[25];
  scanf("%s", s);
  n = strlen(s);
  for (i = 0; i < n; i++) {
    ara[s[i] - 97]++;
  }
  for (i = 0; i < 26; i++) {
    if (ara[i] == 0)
      count += (n + 1);
    else
      count += (n + 1 - ara[i]);
  }
  printf("%d", count);
  return 0;
}
