14b.c

   1 #include <stdio.h>
   2 #include <stdbool.h>
   3 #include <limits.h>
   4 #include <string.h>
   5
   6 #define lookup(i, x1, x2) (i)[((x1)-'A')+((x2)-'A')*26]
   7
   8 int main()
   9 {
  10         char *buf = NULL;
  11         size_t len;
  12         char template[26*26] = {0};
  13         unsigned long input1[26*26] = {0};
  14         unsigned long input2[26*26] = {0};
  15         unsigned long *input = input1;
  16         unsigned long *newinput = input2;
  17
  18         int first = getchar();
  19         int c, oldc = first;
  20         unsigned long freq[26] = {0};
  21         while ( (c = getchar()) != '\n') {
  22                 lookup(input, oldc, c) = 1;
  23                 oldc = c;
  24         }
  25
  26         while (getline(&buf, &len, stdin) != -1) {
  27                 if (buf[0] == '\n')
  28                         continue;
  29                 lookup(template, buf[0], buf[1]) = buf[6];
  30         }
  31
  32         for (int step = 0; step < 40; step++) {
  33                 for (char x = 'A'; x<='Z'; x++) {
  34                         for (char y = 'A'; y<='Z'; y++) {
  35                                 char ins = lookup(template, x, y);
  36                                 if (ins != '\0') {
  37                                         unsigned long freq = lookup(input, x, y);
  38                                         lookup(newinput, x, ins) += freq;
  39                                         lookup(newinput, ins, y) += freq;
  40                                 }
  41                         }
  42                 }
  43                 unsigned long *t = newinput;
  44                 newinput = input;
  45                 input = t;
  46                 memset(&newinput[0], 0, sizeof(input1));
  47         }
  48
  49         for (char x = 'A'; x<='Z'; x++) {
  50                 for (char y = 'A'; y<='Z'; y++) {
  51                         freq[x-'A'] += lookup(input, x, y);
  52                         freq[y-'A'] += lookup(input, x, y);
  53                 }
  54         }
  55         freq[first-'A']++;
  56         freq[oldc-'A']++;
  57
  58         unsigned long min = ULONG_MAX, max = 0;
  59         for (int i = 0; i<26; i++) {
  60                 max = freq[i] > max ? freq[i] : max;
  61                 min = freq[i] > 1 && freq[i] < min ? freq[i] : min;
  62         }
  63
  64         printf("%lu\n", max/2-min/2);
  65 }