Poj1961 KMP Algorithm

Poj1961

Repeat the problem:

Enter a string s with a length of L to obtain the prefix of all s consisting of repeated strings, and output the length of the prefix and the maximum repetition of the prefix.

AC code:

 1 //Memory: 5700K        Time: 641MS 2 #include <iostream> 3 #include <cstring> 4 #include <string> 5  6 using namespace std; 7  8 const int maxn = 1000010; 9 10 int prefix[maxn];11 string s;12 13 void init()14 {15     int l = s.size();16     memset(prefix, 0, sizeof(prefix));17     int k = 0;18     for (int i = 2; i <= l; i++) {19         while (k > 0 && s[k] != s[i - 1])20             k = prefix[k];21         if (s[k] == s[i - 1])22             k++;23         prefix[i] = k;24     }25 }26 27 int main()28 {29     int n;30     int case_num = 1;31     while (cin >> n && n) {32         cin >> s;33         init();34         int l = s.size();35         cout << "Test case #" << case_num++ << endl;36         for (int k = 1; k <= l; k++) {37             if ( prefix[k] != 0 && k % (k - prefix[k]) == 0) {38                 cout << k << " " << k / (k - prefix[k]) << endl;39             }40         }41         cout << endl;42     }43     return 0;44 }

 

Poj1961 KMP Algorithm