t组数据 求模式串在文本串中的出现次数（允许重叠）
1 #include <cstdio> 2 #include <cstring> 3 #include <algorithm> 4 using namespace std; 5 typedef long long LL; 6 7 const int maxm = 1e4 + 10; 8 const int maxn = 1e6 + 10; 9 char P[maxm], T[maxn]; 10 int f[maxm]; 11 12 int Tc, N, M; 13 int ans; 14 15 void getFail(char* p, int *f) { 16 f[0] = 0; 17 f[1] = 0; 18 for (int i = 1; i < M; i++) { 19 int j = f[i]; 20 while (j && P[i] != P[j]) j = f[j]; 21 f[i + 1] = P[i] == P[j] ? j + 1 : 0; 22 } 23 } 24 25 void find(char* T, char* P, int* f) { 26 int j = 0; 27 for (int i = 0; i < N; i++) { 28 while (j && P[j] != T[i]) j = f[j]; 29 if (P[j] == T[i]) j++; 30 if (j == M) { 31 ans++; 32 if (j != 1) { 33 i--; 34 j--; 35 j = f[j]; 36 } 37 38 } 39 } 40 } 41 42 int main() { 43 scanf("%d", &Tc); 44 while (Tc--) { 45 ans = 0; 46 scanf("%s", P); 47 scanf("%s", T); 48 N = strlen(T); 49 M = strlen(P); 50 getFail(P, f); 51 find(T, P, f); 52 printf("%d ", ans); 53 } 54 55 return 0; 56 }