Codeforces Round #344 (Div. 2) D. Messenger CF631D

好久没写KMP
根本想不到这种做法

首先先对连续相同的合并一下

假设s字符个数为1那么只要长度足够并且字符相同就合法

假设s字符个数为2那么左右两边长度都够就可以
但是只有一个位置合法 不能左移或者右移

假设s字符个数>=3 那么需要首尾两个长度足够 并且中间的全部相等才行
所以对自身getfail 然后再用t匹配
需要注意首尾的是需要判长度足够就行
所以需要改一下特判

#include <iostream>#include <algorithm>#include <sstream>#include <string>#include <queue>#include <cstdio>#include <map>#include <set>#include <utility>#include <stack>#include <cstring>#include <cmath>#include <vector>#include <ctime>#include <bitset>using namespace std;#define pb push_back#define sd(n) scanf("%d",&n)#define sdd(n,m) scanf("%d%d",&n,&m)#define sddd(n,m,k) scanf("%d%d%d",&n,&m,&k)#define sld(n) scanf("%lld",&n)#define sldd(n,m) scanf("%lld%lld",&n,&m)#define slddd(n,m,k) scanf("%lld%lld%lld",&n,&m,&k)#define sf(n) scanf("%lf",&n)#define sff(n,m) scanf("%lf%lf",&n,&m)#define sfff(n,m,k) scanf("%lf%lf%lf",&n,&m,&k)#define ss(str) scanf("%s",str)#define ans() printf("%d",ans)#define ansn() printf("%d\n",ans)#define anss() printf("%d ",ans)#define lans() printf("%lld",ans)#define lanss() printf("%lld ",ans)#define lansn() printf("%lld\n",ans)#define fansn() printf("%.10f\n",ans)#define r0(i,n) for(int i=0;i<(n);++i)#define r1(i,e) for(int i=1;i<=e;++i)#define rn(i,e) for(int i=e;i>=1;--i)#define rsz(i,v) for(int i=0;i<(int)v.size();++i)#define szz(x) ((int)x.size())#define mst(abc,bca) memset(abc,bca,sizeof abc)#define lowbit(a) (a&(-a))#define all(a) a.begin(),a.end()#define pii pair<int,int>#define pli pair<ll,int>#define pll pair<ll,ll>#define mp make_pair#define lrt rt<<1#define rrt rt<<1|1#define X first#define Y second#define PI (acos(-1.0))#define sqr(a) ((a)*(a))typedef long long ll;typedef unsigned long long ull;const ll mod = 1000000000+7;const double eps=1e-9;const int inf=0x3f3f3f3f;const ll infl = 10000000000000000;const int maxn=  200000+10;const int maxm = 40000+10;//Pretests passedint in(int &ret){    char c;    int sgn ;    if(c=getchar(),c==EOF)return -1;    while(c!='-'&&(c<'0'||c>'9'))c=getchar();    sgn = (c=='-')?-1:1;    ret = (c=='-')?0:(c-'0');    while(c=getchar(),c>='0'&&c<='9')ret = ret*10+(c-'0');    ret *=sgn;    return 1;}struct node{    ll l;    char ch;    bool operator ==(const node &o)    {        return l==o.l&&ch==o.ch;    }    bool operator <= (const node &o)    {        return l<=o.l&&ch==o.ch;    }};node t[maxn],s[maxn];int n,m;void init(){    int j = 0;    for(int i=0;i<n;++i)    {        if(j==0||t[j-1].ch!=t[i].ch)t[j++] = t[i];        else t[j-1].l+=t[i].l;    }    n = j;    j = 0;    for(int i=0;i<m;++i)    {        if(j==0||s[j-1].ch!=s[i].ch)s[j++] = s[i];        else s[j-1].l+=s[i].l;    }    m = j;}int nt[maxn];int main(){#ifdef LOCAL    freopen("input.txt","r",stdin);//    freopen("output.txt","w",stdout);#endif // LOCAL//    int n,m;    sdd(n,m);    r0(i,n) scanf("%lld-%c",&t[i].l,&t[i].ch);    r0(i,m) scanf("%lld-%c",&s[i].l,&s[i].ch);    init();    ll ans = 0;    if(m==1)    {        r0(i,n)        {            if(s[0]<=t[i])ans+=t[i].l-s[0].l+1;        }    }    else if(m==2)    {        r0(i,n-1)        {            if(s[0]<=t[i]&&s[1]<=t[i+1])++ans;        }    }    else    {        nt[1] = 0;        for(int i = 2 ; i < m - 1 ; ++i)        {            int j = nt[i-1];            while(j&&! (s[j+1]==s[i]) )j = nt[j];            if(s[j+1]==s[i])++j;            nt[i] = j;        }        for(int i = 1, j = 0 ; i<n-1;++i)        {            while(j&&!(s[j+1]==t[i]))j = nt[j];            if(s[j+1]==t[i])++j;            if(j==m-2)            {                if(s[0]<=t[i-j]&&s[j+1]<=t[i+1])++ans;                j = nt[j];            }        }    }    lansn();    return 0;}