Luogu2375 [NOI2014]动物园（KMP）

系统管理员 2021-11-17 05:12 379阅读 0赞

# 写炸，上网，不同KMP形态。 #

# 无力，照该，一换写法就过。 #

横批：我是垃圾  
求\\(next\\)时\\(DP\\)出\\(num\\)，路径压缩防卡\\(n^2\\)

#include <iostream> #include <cstdio> #include <cstring> #include <algorithm> #include <cmath> #define R(a,b,c) for(register int a = (b); a <= (c); ++ a) #define nR(a,b,c) for(register int a = (b); a >= (c); -- a) #define Max(a,b) ((a) > (b) ? (a) : (b)) #define Min(a,b) ((a) < (b) ? (a) : (b)) #define Fill(a,b) memset(a, b, sizeof(a)) #define Abs(a) ((a) < 0 ? -(a) : (a)) #define Swap(a,b) a^=b^=a^=b #define ll long long #define ON_DEBUG #ifdef ON_DEBUG #define D_e_Line printf("\n\n----------\n\n") #define D_e(x) cout << #x << " = " << x << endl #define Pause() system("pause") #define FileOpen() freopen("in.txt","r",stdin); #else #define D_e_Line ; #define D_e(x) ; #define Pause() ; #define FileOpen() ; #endif struct ios{ template<typename ATP>ios& operator >> (ATP &x){ x = 0; int f = 1; char c; for(c = getchar(); c < '0' || c > '9'; c = getchar()) if(c == '-') f = -1; while(c >= '0' && c <= '9') x = x * 10 + (c ^ '0'), c = getchar(); x*= f; return *this; } }io; using namespace std; const int N = 1000007; const int mod = 1000000007; int nxt[N], num[N]; char str[N]; int main() { //FileOpen(); int n; io >> n; while(n--) { scanf("%s", str); int len = strlen(str); int ans = 1; R(i,1,len) nxt[i] = 0; nxt[0] = -1; num[0] = 0, num[1] = 1; int i = 0, j = -1; while(i < len){ if(j == -1 || str[i] == str[j]){ nxt[++i] = ++j; num[i] = num[j] + 1; } else j = nxt[j]; } i = 0, j = -1; while(i < len){ if(j == -1 || str[i] == str[j]){ ++i, ++j; while((j << 1) > i + 1) j = nxt[j]; ans = ans * 1ll * (num[j] + 1) % mod; } else j = nxt[j]; } printf("%d\n", ans); } return 0; }

全\\(WA\\)的原始代码

![1570282-20190724194825162-173458523.png][]

转载于:https://www.cnblogs.com/bingoyes/p/11240421.html

[1570282-20190724194825162-173458523.png]: /images/20211116/c810230dc80f45df8ee30f4ac8fc2b11.png