bzoj1898: [Zjoi2005]Swamp 沼泽鳄鱼

一眼矩乘

把图分成12个，然后直接搞。

#include<cstdio>
#include<iostream>
#include<cstring>
#include<cstdlib>
#include<algorithm>
#include<cmath>
using namespace std;
typedef long long LL;
const LL mod=10000;

int n;
struct Matrix
{
    LL a[60][60];
    Matrix(){}
    void clean()
    {
        memset(a,0,sizeof(a));
    }
    void beone()
    {
        clean();
        for(int i=1;i<=n;i++)a[i][i]=1;
    }
    friend Matrix operator *(Matrix A,Matrix B)
    {
        Matrix C;C.clean();
        for(int i=1;i<=n;i++)
            for(int j=1;j<=n;j++)
                for(int k=1;k<=n;k++)
                    C.a[i][j]=(C.a[i][j]+(A.a[i][k]*B.a[k][j])%mod)%mod;
        return C;
    }
}G[12];

LL mp[60][60];
int main()
{
    freopen("swamp.in","r",stdin);
    freopen("swamp.out","w",stdout);
    int m,st,ed,x,y;LL K;
    scanf("%d%d%d%d%lld",&n,&m,&st,&ed,&K);st++,ed++;
    memset(mp,0,sizeof(mp));
    for(int i=1;i<=m;i++)
    {
        scanf("%d%d",&x,&y);x++,y++;
        mp[x][y]=1;mp[y][x]=1;
    }
    for(int k=0;k<=11;k++)
        for(int i=1;i<=n;i++)
            for(int j=1;j<=n;j++)
                G[k].a[i][j]=mp[i][j];
    
    int fish;LL p;
    scanf("%d",&fish);
    for(int i=1;i<=fish;i++)
    {
        scanf("%lld",&p);
        for(int j=1;j<=p;j++)
        {
            scanf("%d",&x);x++;
            for(int k=j-1;k<=11;k+=p)
            {
                for(int u=1;u<=n;u++)G[k].a[u][x]=0;
            }
        }
    }
    Matrix YZH;YZH.beone();
    for(int i=1;i<=12;i++)
    {
        YZH=YZH*G[i%12];
        if(K==i){printf("%lld
",YZH.a[st][ed]);return 0;}
    }
    p=K/12;K%=12;
    Matrix ans;ans.beone();
    while(p!=0)
    {
        if(p%2==1)ans=ans*YZH;
        YZH=YZH*YZH;p/=2;
    }
    for(int i=1;i<=K;i++)ans=ans*G[i];
    printf("%lld
",ans.a[st][ed]);
    return 0;
}