SPOJ/FILRTEST - 7423. File Recover Testing/filrtest.cpp

   1 using namespace std;
   2 #include <cstdio>
   3 #include <cstring>
   4
   5 const int MAXN = 1000010;
   6 char s[MAXN];
   7 int border[MAXN];
   8
   9 int maximum_repetitions(int n, int k) {
  10     if (k < n) return 0;
  11
  12     border[0] = -1;
  13     for (int i = 0; i < n; ++i) {
  14         border[i+1] = border[i];
  15         while (border[i+1] > -1 and s[border[i+1]] != s[i]) border[i+1] = border[border[i+1]];
  16         border[i+1]++;
  17     }
  18
  19     return 1 + (k - n) / (n - border[n]);
  20 }
  21
  22 int main(){
  23     int k;
  24     while (scanf("%d %s", &k, s) == 2) {
  25         if (k == -1) break;
  26         int n = strlen(s);
  27         printf("%d\n", maximum_repetitions(n, k));
  28     }
  29     return 0;
  30 }