POJ PKU 2778

题解在我的百度博客：http://hi.baidu.com/%D2%D5%C1%D6010/blog/item/6db06ccf0a3b440993457e7b.html 

#include<iostream>using namespace std;const int Mod = 100000;const int size = 120;__int64 g[size][size];struct Node{ int fail,son[4],end; void Init() { fail = -1; memset(son, -1, sizeof(son)); end = 0; }}node[size];int node_Num = 0;int q[size], head, tail;int Index(char a){ switch (a) { case 'A':return 0; case 'G':return 1; case 'C':return 2; case 'T':return 3; }}void Insert(char *s){ int p=0; for (int i=0; s[i]; i++) { if (node[p].end) break; if (node[p].son[Index(s[i])] == -1) { node_Num++; node[p].son[Index(s[i])] = node_Num; node[node_Num].Init(); } p = node[p].son[Index(s[i])]; } node[p].end++;}void Build_Ac(){ head = tail = 0; int temp = 0, p = 0, i; q[tail++] = 0; while (head < tail) { temp = q[head++]; for (i = 0; i < 4; i++) if (node[temp].son[i] != -1) { if (temp == 0) node[node[temp].son[i]].fail = 0; else { p = node[temp].fail; while (p != -1) { if (node[p].son[i] != -1) { node[node[temp].son[i]].fail = node[p].son[i]; if (node[node[p].son[i]].end) node[node[temp].son[i]].end++; break; } p = node[p].fail; } if (p == -1) node[node[temp].son[i]].fail = 0; } q[tail++] = node[temp].son[i]; } }}void MatrixMul(__int64 b[][size], __int64 c[][size], int sz){ int i, j, k; __int64 temp[size][size] = {0}; for (i = 0; i < sz; i++) for (j = 0; j < sz; j++) for (k = 0; k < sz; k++) { temp[i][j] += b[i][k]*c[k][j]; if (temp[i][j] >= Mod) temp[i][j] %= Mod; } for (i = 0; i < sz; i++) for (j = 0; j < sz; j++) b[i][j] = temp[i][j];}void MatrixPow(__int64 tot[][size], __int64 a[][size], int sz, int n){ while (n > 0) { if (n&1) MatrixMul(tot,a, sz); MatrixMul(a, a, sz); n >>= 1; }}int N = 2000000000;int M;char word[14];__int64 tot[size][size];int main(){ int i, j; while (scanf("%d%d", &M, &N) != EOF) { node_Num = 0; node[0].Init(); memset(g, 0, sizeof(g)); for (i = 0; i < M; i++) { scanf("%s", word); Insert(word); } Build_Ac(); node_Num++; for (i = 0; i < node_Num; i++) if(!node[i].end) for (j = 0; j < 4; j++) { if (node[i].son[j] != -1 && node[node[i].son[j]].end==0) g[i][node[i].son[j]]++; else if (node[i].son[j]== -1) { if (i==0) g[0][0]++; else { int temp = i; while (node[temp].son[j]== -1) { if (temp==0)break; temp = node[temp].fail; } if(node[temp].son[j] != -1 && node[node[temp].son[j]].end==0) g[i][node[temp].son[j]]++; else if (node[temp].son[j]== -1&& temp==0) g[i][0]++; } } } memset(tot, 0, sizeof(tot)); for (i = 0; i < node_Num; i++) tot[i][i] = 1; MatrixPow(tot, g, node_Num, N); __int64 ans = 0; for (i = 0; i < node_Num; i++) if (node[i].end==0) { ans += tot[0][i]; if (ans>=Mod) ans %= Mod; } printf("%I64d/n",ans); } return 0;} 

/*这个自动机自我感觉比上一个好，而且在构造矩阵时更加方便。但是，提交后，时间居然还要多20多ms-_-//*/#include<iostream>using namespace std;const int Mod = 100000;const int size =110;const int kind = 4;__int64 g[size][size];struct Node{ int fail,son[kind],end; void Init() { fail = -1; memset(son, -1, sizeof(son)); end = 0; }}node[size];int node_Num = 0;int q[size], head, tail;int Index(char a){ switch (a) { case 'A':return 0; case 'G':return 1; case 'C':return 2; case 'T':return 3; } }void Insert(char *s){ int p=0; for (int i=0; s[i]; i++) { if (node[p].end) break; if (node[p].son[Index(s[i])] == -1) { node_Num++; node[p].son[Index(s[i])] = node_Num; node[node_Num].Init(); } p = node[p].son[Index(s[i])]; } node[p].end++;}void Build_Ac(){ head = tail = 0; int temp = 0, p = 0, i; q[tail++] = 0; while (head < tail) { temp = q[head++]; for (i = 0; i < kind; i++) { p = node[temp].son[i]; if (p != -1) { if (temp == 0) node[p].fail = 0; else { node[p].fail = node[node[temp].fail].son[i]; if (node[node[p].fail].end) node[p].end++; } q[tail++] = node[temp].son[i]; } else { if (temp == 0) node[temp].son[i] = 0; else node[temp].son[i] = node[node[temp].fail].son[i]; } } }}void MatrixMul(__int64 b[][size], __int64 c[][size], int sz){ int i, j, k; __int64 temp[size][size] = {0}; for (i = 0; i < sz; i++) for (j = 0; j < sz; j++) for (k = 0; k < sz; k++) { temp[i][j] += b[i][k]*c[k][j]; if (temp[i][j] >= Mod) temp[i][j] %= Mod; } for (i = 0; i < sz; i++) for (j = 0; j < sz; j++) b[i][j] = temp[i][j];}void MatrixPow(__int64 tot[][size], __int64 a[][size], int sz, int n){ while (n > 0) { if (n&1) MatrixMul(tot,a, sz); MatrixMul(a, a, sz); n >>= 1; }}int N;int M;char word[14];__int64 tot[size][size], Ans, ans;int main(){ int i, j; while (scanf("%d%d", &M, &N) != EOF) { node_Num = 0; Ans = ans = 0; node[0].Init(); memset(g, 0, sizeof(g)); for (i = 0; i < M; i++) { scanf("%s", word); Insert(word); } Build_Ac(); node_Num++; for (i = 0; i < node_Num; i++) if(!node[i].end) for (j = 0; j < kind; j++) { if (node[node[i].son[j]].end==0) g[i][node[i].son[j]]++; } memset(tot, 0, sizeof(tot)); for (i = 0; i < node_Num; i++) tot[i][i] = 1; MatrixPow(tot, g, node_Num, N); for (i = 0; i < node_Num; i++) if (node[i].end==0) { ans += tot[0][i]; if (ans>=Mod) ans %= Mod; } printf("%I64d/n",ans); } return 0;}