本文共 2040 字,大约阅读时间需要 6 分钟。
10天前交的题,当时OJ挂了,现在才想起去看结果。
如果在状态上深搜的过程中出现了环,说明可以无限长。
//#pragma comment(linker, "/STACK:1024000000,1024000000")#include #include #include #include #include #include #include #include #include #include #include #include #include #include using namespace std;typedef long long ll;typedef unsigned long long ull;typedef pair pii;#define pb(a) push_back(a)#define INF 0x1f1f1f1f#define lson idx<<1,l,mid#define rson idx<<1|1,mid+1,r#define PI 3.1415926535898template T min(const T& a,const T& b,const T& c) { return min(min(a,b),min(a,c));}template T max(const T& a,const T& b,const T& c) { return max(max(a,b),max(a,c));}void debug() {#ifdef ONLINE_JUDGE#else freopen("in.txt","r",stdin); // freopen("d:\\out1.txt","w",stdout);#endif}int getch() { int ch; while((ch=getchar())!=EOF) { if(ch!=' '&&ch!='\n')return ch; } return EOF;}const int MAX_NODE=500000;const int SIGMA_SIZE=26;int ch[MAX_NODE][SIGMA_SIZE];int fail[MAX_NODE];int val[MAX_NODE];char dmc[MAX_NODE];int sz;int idx(char c){ return c-'A';}void init(){ sz=1; memset(ch[0],0,sizeof(ch[0])); val[0]=0;}void insert(const char *s){ int u=0; for(int i=0;s[i]!='\0';i++) { int c=idx(s[i]); if(!ch[u][c]) { memset(ch[sz],0,sizeof(ch[sz])); val[sz]=0; dmc[sz]=s[i]; ch[u][c]=sz++; } u=ch[u][c]; } val[u]=1;}void construct(){ queue q; fail[0]=0; for(int c=0;c =0;c--) { int v=ch[u][c]; if(!val[v]) { if(f(v)+1>dp[u]) { dp[u]=f(v)+1; road[u]=c; } } if(!flag)return 0; } vis[u]=1; return dp[u];}int main(){ // debug(); int t; scanf("%d",&t); for(int ca=1;ca<=t;ca++) { scanf("%d%d",&n,&m); init(); for(int i=1;i<=m;i++) { char buf[100]; scanf("%s",buf); insert(buf); } construct(); memset(vis,0,sizeof(vis)); flag=1; int num=f(0); if(!flag||!num)printf("No\n"); else { int u=0; while(num--) { printf("%c",road[u]+'A'); u=ch[u][road[u]]; } printf("\n"); } // printf("%d %d\n",num,flag); } return 0;}
转载于:https://www.cnblogs.com/BMan/p/3453767.html