BZOJ3942 [Usaco2015 Feb]Censoring

 1 /**************************************************************
 2     Problem: 3942
 3     User: rausen
 4     Language: C++
 5     Result: Accepted
 6     Time:224 ms
 7     Memory:11548 kb
 8 ****************************************************************/
 9  
10 #include <cstdio>
11 #include <cstring>
12  
13 using namespace std;
14 const int N = 1e6 + 5;
15  
16 char s1[N], s2[N], s[N];
17 int next[N], a[N], top;
18  
19 int main() {
20     int i, j, len;
21     gets(s1 + 1), gets(s2 + 1);
22     len = strlen(s2 + 1);
23     for (i = 2, j = next[1] = 0; s2[i]; ++i) {
24         while (j && s2[i] != s2[j + 1]) j = next[j];
25         if (s2[i] == s2[j + 1]) ++j;
26         next[i] = j;
27     }
28     for (i = 1; s1[i]; ++i) {
29         j = a[top], s[++top] = s1[i];
30         while (j && s2[j + 1] != s[top]) j = next[j];
31         if (s[top] == s2[j + 1]) ++j;
32         a[top] = j;
33         if (a[top] == len) top -= len;
34     }
35     s[top + 1] = ‘\0‘;
36     puts(s + 1);
37     return 0;
38 }