跳过正文
  1. Posts/

poj 2752 Seek the Name, Seek the Fame (kmp 理解nxt函数)

·1 分钟

poj 2752题目链接

题意:求出所有的前缀和后缀相同的子串的长度。

思路:求出nxt函数,观察发现,从从len递归向前就是答案。

 1/* ***********************************************
 2Author :111qqz
 3Created Time :2016年08月10日 星期三 21时05分52秒
 4File Name :code/poj/2752.cpp
 5************************************************ */
 6
 7#include <cstdio>
 8#include <cstring>
 9#include <iostream>
10#include <algorithm>
11#include <vector>
12#include <queue>
13#include <stack>
14#include <set>
15#include <map>
16#include <string>
17#include <cmath>
18#include <cstdlib>
19#include <deque>
20#include <ctime>
21#define fst first
22#define sec second
23#define lson l,m,rt<<1
24#define rson m+1,r,rt<<1|1
25#define ms(a,x) memset(a,x,sizeof(a))
26typedef long long LL;
27#define pi pair < int ,int >
28#define MP make_pair
29
30using namespace std;
31const double eps = 1E-8;
32const int dx4[4]={1,0,0,-1};
33const int dy4[4]={0,-1,1,0};
34const int inf = 0x3f3f3f3f;
35const int N=4E6+7;
36int n;
37string a;
38int nxt[N];
39void getnxt( int n)
40{
41    int i = 0 ;
42    int j = -1 ;
43    nxt[0] = -1;
44    while (i<n)
45	if (j==-1||a[i]==a[j]) nxt[++i]=++j;
46	else j = nxt[j];
47}
48void print( int x)
49{
50    if (nxt[x]!=-1)
51    {
52	print(nxt[x]);
53	printf("%d ",x);
54    }
55}
56int main()
57{
58	#ifndef  ONLINE_JUDGE
59	freopen("code/in.txt","r",stdin);
60  #endif
61//	ios::sync_with_stdio(false);
62	while (cin>>a)
63	{
64	    int len = a.length();
65	    getnxt(len);
66	  //  for ( int i = 0 ; i < len ; i++) cout<<i<<" nxt[i]:"<<nxt[i]<<endl;
67	    print(nxt[len]);
68	    printf("%d\n",len);
69
70	}
71
72  #ifndef ONLINE_JUDGE
73  fclose(stdin);
74  #endif
75    return 0;
76}

相关文章

whust 2016 #1 D Zhenya moves from the dormitory (贪心,模拟)

·1 分钟
题目链接 傻逼模拟。。读完题就ac了。。。 1/* *********************************************** 2Author :111qqz 3Created Time :2016年08月07日 星期日 18时04分18秒 4File Name :code/whust2016/#1/D.cpp 5************************************************ */ 6#include <cstdio> 7#include <cstring> 8#include <iostream> 9#include <algorithm> 10#include <vector> 11#include <queue> 12#include <stack> 13#include <set> 14#include <map> 15#include <string> 16#include <cmath> 17#include <cstdlib> 18#include <deque> 19#include <ctime> 20#define fst first 21#define sec second 22#define lson l,m,rt<<1 23#define rson m+1,r,rt<<1|1 24#define ms(a,x) memset(a,x,sizeof(a)) 25typedef long long LL; 26#define pi pair < int ,int > 27#define MP make_pair 28using namespace std; 29const double eps = 1E-8; 30const int dx4[4]={1,0,0,-1}; 31const int dy4[4]={0,-1,1,0}; 32const int inf = 0x3f3f3f3f; 33const int N=280; 34int n,m; 35int total,adva,advb; 36struct Friend 37{ 38 int money; 39 int adv; 40}f[N]; 41struct Room 42{ 43 int type; 44 int cost; 45 int adv; 46}r[N]; 47struct Ans 48{ 49 int val; 50 int rid; 51 int fid; 52 bool operator < (Ans b)const 53 { 54 return val>b.val; 55 } 56}ans[300*300]; 57int main() 58{ 59 #ifndef ONLINE_JUDGE 60 freopen("code/in.txt","r",stdin); 61 #endif 62 cin>>total>>adva>>advb; 63 cin>>n; 64 for ( int i = 1 ; i <= n ; i++) 65 scanf("%d %d",&f[i].money,&f[i].adv); 66 scanf("%d",&m); 67 for ( int i = 1 ; i <= m ; i++) 68 scanf("%d%d%d",&r[i].type,&r[i].cost,&r[i].adv); 69 int cnt = 0 ; 70 for ( int i = 1 ; i <= m ; i++) 71 { 72 if (r[i].type==1) 73 { 74 if (r[i].cost<=total) 75 { 76 cnt++; 77 ans[cnt].val = r[i].adv+adva; 78 ans[cnt].rid = i; 79 ans[cnt].fid = -1; 80 } 81 continue; 82 } 83 else 84 { 85 for ( int j = 0 ; j <= n ; j++) 86 { 87 if (j==0) //自己住双人间 88 { 89 if (r[i].cost<=total) 90 { 91 cnt++; 92 ans[cnt].val = r[i].adv+advb; 93 ans[cnt].rid = i ; 94 ans[cnt].fid = -1; 95 } 96 } 97 else 98 { 99 if (r[i].cost<=total*2&&r[i].cost<=f[j].money*2) 100 { 101 cnt++; 102 ans[cnt].val = r[i].adv+f[j].adv; 103 ans[cnt].rid = i ; 104 ans[cnt].fid = j; 105 } 106 } 107 } 108 } 109 } 110// for ( int i = 1 ; i <= cnt ; i++) 111// { 112// printf("val:%d room: %d friend : %d \n",ans[i].val,ans[i].rid,ans[i].fid); 113// } 114 if (cnt==0) 115 { 116 puts("Forget about apartments. Live in the dormitory."); 117 }else 118 { 119 sort(ans+1,ans+cnt+1); 120 if (r[ans[1].rid].type==1) 121 { 122 printf("You should rent the apartment #%d alone.\n",ans[1].rid); 123 } 124 else 125 { 126 if (ans[1].fid==-1) 127 { 128 printf("You should rent the apartment #%d alone.\n",ans[1].rid); 129 } 130 else 131 { 132 133 printf("You should rent the apartment #%d with the friend #%d.\n",ans[1].rid,ans[1].fid); 134 135 } 136 } 137 } 138 #ifndef ONLINE_JUDGE 139 fclose(stdin); 140 #endif 141 return 0; 142}