BCD Code ZOJ

题意: 

问A到B之间的所有整数,转换成BCD Code后,

有多少个不包含属于给定病毒串集合的子串,A,B <=10^200,病毒串总长度<= 2000.

BCD码这个在数字电路课上讲了,题干也讲的很详细。

数位DP的实现是通过0~9 ,并不是通过BCD码

所有我们需要先把字串放入AC自动机,建立一个BCD数组

因为BCD码是一个4位二进制数,但是tire图上全是0,1,

所以对于一个数字,我们的要在转移4次,

如果中间出现了病毒串就return -1 表示不能转移,

BCD【i】【j】表示在AC自动机 i 这个节点转移到数字 j 对应的在AC自动机上的节点标号。

  然后就是简单的数位DP了,然而我写搓了,由于没有前导0所以前导0要处理掉。

但是你不转移的时候,不能 bcd[idx][i] != -1 就直接continue ,

因为有0的情况,i==0 但是(bcd[idx][i] == -1) 但是这个0是前导0所以不影响。

  1 #include <set>
  2 #include <map>
  3 #include <stack>
  4 #include <queue>
  5 #include <cmath>
  6 #include <ctime>
  7 #include <cstdio>
  8 #include <string>
  9 #include <vector>
 10 #include <cstring>
 11 #include <iostream>
 12 #include <algorithm>
 13 
 14 #define  pi    acos(-1.0)
 15 #define  eps   1e-9
 16 #define  fi    first
 17 #define  se    second
 18 #define  rtl   rt<<1
 19 #define  rtr   rt<<1|1
 20 #define  bug                printf("******
")
 21 #define  mem(a, b)          memset(a,b,sizeof(a))
 22 #define  name2str(x)        #x
 23 #define  fuck(x)            cout<<#x" = "<<x<<endl
 24 #define  sfi(a)             scanf("%d", &a)
 25 #define  sffi(a, b)         scanf("%d %d", &a, &b)
 26 #define  sfffi(a, b, c)     scanf("%d %d %d", &a, &b, &c)
 27 #define  sffffi(a, b, c, d) scanf("%d %d %d %d", &a, &b, &c, &d)
 28 #define  sfL(a)             scanf("%lld", &a)
 29 #define  sffL(a, b)         scanf("%lld %lld", &a, &b)
 30 #define  sfffL(a, b, c)     scanf("%lld %lld %lld", &a, &b, &c)
 31 #define  sffffL(a, b, c, d) scanf("%lld %lld %lld %lld", &a, &b, &c, &d)
 32 #define  sfs(a)             scanf("%s", a)
 33 #define  sffs(a, b)         scanf("%s %s", a, b)
 34 #define  sfffs(a, b, c)     scanf("%s %s %s", a, b, c)
 35 #define  sffffs(a, b, c, d) scanf("%s %s %s %s", a, b,c, d)
 36 #define  FIN                freopen("../in.txt","r",stdin)
 37 #define  gcd(a, b)          __gcd(a,b)
 38 #define  lowbit(x)          x&-x
 39 #define  IO                 iOS::sync_with_stdio(false)
 40 
 41 
 42 using namespace std;
 43 typedef long long LL;
 44 typedef unsigned long long ULL;
 45 const ULL seed = 13331;
 46 const LL INFLL = 0x3f3f3f3f3f3f3f3fLL;
 47 const int maxn = 1e6 + 7;
 48 const int maxm = 8e6 + 10;
 49 const int INF = 0x3f3f3f3f;
 50 const int mod = 1000000009;
 51 int T, n;
 52 char buf[maxn], num1[maxn], num2[maxn];
 53 int bcd[2020][12], bit[maxn];
 54 LL dp[205][2020];
 55 
 56 struct Aho_Corasick {
 57     int next[2010][2], fail[2010], End[2010];
 58     int root, cnt;
 59 
 60     int newnode() {
 61         for (int i = 0; i < 2; i++) next[cnt][i] = -1;
 62         End[cnt++] = 0;
 63         return cnt - 1;
 64     }
 65 
 66     void init() {
 67         cnt = 0;
 68         root = newnode();
 69     }
 70 
 71     void insert(char buf[]) {
 72         int len = strlen(buf);
 73         int now = root;
 74         for (int i = 0; i < len; i++) {
 75             if (next[now][buf[i] - '0'] == -1) next[now][buf[i] - '0'] = newnode();
 76             now = next[now][buf[i] - '0'];
 77         }
 78         End[now] = 1;
 79     }
 80 
 81     void build() {
 82         queue<int> Q;
 83         fail[root] = root;
 84         for (int i = 0; i < 2; i++)
 85             if (next[root][i] == -1) next[root][i] = root;
 86             else {
 87                 fail[next[root][i]] = root;
 88                 Q.push(next[root][i]);
 89             }
 90         while (!Q.empty()) {
 91             int now = Q.front();
 92             Q.pop();
 93             if (End[fail[now]]) End[now] = 1;
 94             for (int i = 0; i < 2; i++)
 95                 if (next[now][i] == -1) next[now][i] = next[fail[now]][i];
 96                 else {
 97                     fail[next[now][i]] = next[fail[now]][i];
 98                     Q.push(next[now][i]);
 99                 }
100         }
101     }
102 
103     int get_num(int cur, int num) {
104         if (End[cur]) return -1;
105         int now = cur;
106         for (int i = 3; i >= 0; --i) {
107             if (End[next[now][1 & (num >> i)]]) return -1;
108             now = next[now][1 & (num >> i)];
109         }
110         return now;
111     }
112 
113     void get_bcd() {
114         for (int i = 0; i < cnt; ++i)
115             for (int j = 0; j < 10; ++j)
116                 bcd[i][j] = get_num(i, j);
117     }
118 
119     LL dfs(int pos, int idx, int flag, int limit) {
120         if (pos == -1) return 1;
121         if (!limit && dp[pos][idx] != -1) return dp[pos][idx];
122         int num = limit ? bit[pos] : 9;
123         LL ans = 0;
124         for (int i = 0; i <= num; ++i) {
125             if (flag && i == 0) ans = (ans + dfs(pos - 1, idx, 1, limit && i == num)) % mod;
126             else if (bcd[idx][i] != -1) ans = (ans + dfs(pos - 1, bcd[idx][i], 0, limit && i == num)) % mod;
127         }
128         if (!limit && !flag) dp[pos][idx] = ans;
129         return ans;
130     }
131     
132     LL solve() {
133         get_bcd();
134         int len1 = strlen(num1), len2 = strlen(num2);
135         for (int i = len1-1; i>=0; --i) {
136             if (num1[i] > '0') {
137                 num1[i]--;
138                 break;
139             } else num1[i] = '9';
140         }
141         for (int i = 0; i < len1; ++i) bit[i] = num1[len1 - 1 - i] - '0';
142         LL ans1 = dfs(len1 - 1, 0, 1, 1);
143         for (int i = 0; i < len2; ++i) bit[i] = num2[len2 - 1 - i] - '0';
144         LL ans2 = dfs(len2 - 1, 0, 1, 1);
145         return (ans2 - ans1 + mod) % mod;
146     }
147 
148     void debug() {
149         for (int i = 0; i < cnt; i++) {
150             printf("id = %3d,fail = %3d,end = %3d,chi = [", i, fail[i], End[i]);
151             for (int j = 0; j < 26; j++) printf("%2d", next[i][j]);
152             printf("]
");
153         }
154     }
155 } ac;
156 
157 int main() {
158    // FIN;
159     sfi(T);
160     while (T--) {
161         sfi(n);
162         ac.init();
163         for (int i = 0; i < n; ++i) {
164             sfs(buf);
165             ac.insert(buf);
166         }
167         ac.build();
168         sffs(num1, num2);
169         mem(dp, -1);
170         printf("%lld
", ac.solve());
171     }
172     return 0;
173 }
View Code
原文地址:https://www.cnblogs.com/qldabiaoge/p/11379682.html