zcmimi's blog
avatar
zc
2019-12-21 19:47:00
  • 本文总阅读量
查看原题

点击跳转

tarjan找出强连通分量之后树形dp

#include<bits/stdc++.h>
namespace ZDY{
    #pragma GCC optimize(3)
    #define il __inline__ __attribute__ ((always_inline))
    #define rg register
    #define ll long long
    #define ull unsigned long long
    #define db double
    #define sht short
    #define MB template <class T>il
    #define Fur(i,x,y) for(int i=x;i<=y;++i)
    #define Fdr(i,x,y) for(int i=x;i>=y;--i)
    #define fl(i,x) for(int i=head[x],to;to=e[i].to,i;i=e[i].nxt)
    #define clr(x,y) memset(x,y,sizeof(x))
    #define cpy(x,y) memcpy(x,y,sizeof(x))
    #define fin(s) freopen(s".in","r",stdin)
    #define fout(s) freopen(s".out","w",stdout)
    #define fcin ios::sync_with_stdio(false)
    #define l2(n) ((int)(log2(n)))
    #define inf 2122219134
    MB T ABS(T x){return x>0?x:-x;}
    MB T MAX(T x,T y){return x>y?x:y;}
    MB T MIN(T x,T y){return x<y?x:y;}
    MB T GCD(T x,T y){return y?GCD(y,x%y):x;}
    MB void SWAP(T &x,T &y){T t=x;x=y;y=t;}
}using namespace ZDY;using namespace std;
namespace IO{const char* ln="\n";const int str=1<<20;struct IN{char buf[str],*s,*t;bool _;IN():s(buf),t(buf),_(0){}il char gc(){return s==t&&((t=(s=buf)+fread(buf,1,str,stdin))==s)?EOF:(*s++);}IN&operator>>(char&ch){if(_)return *this;char c;while((c=gc())!=EOF&&isspace(c));if(c==EOF)_=1;else ch=c;return *this;}IN& operator>>(char* ch){clr(ch,0);if(_)return *this;char c;while((c=gc())!=EOF&&isspace(c));if(c==EOF)return _=1,*this;*ch=c;ch++;while((c=gc())!=EOF&&!isspace(c))*ch=c,ch++;if(c==EOF)_=1;return *this;}IN& operator>>(string& ch){if(_)return *this;char c;while((c=gc())!=EOF&&isspace(c));if(c==EOF)return _=1,*this;ch+=c;while((c=gc())!=EOF&&!isspace(c))ch+=c;if(c==EOF)_=1;return *this;}template<typename T>IN&operator>>(T&x){if(_)return *this;char c=gc();bool ff=0;while(c!=EOF&&(c<'0'||c>'9'))ff^=(c=='-'),c=gc();if(c==EOF){_=1;return *this;}x=0;while(c!=EOF&&'0'<=c&&c<='9')x=(x<<3)+(x<<1)+c-48,c=gc();if(c==EOF)_=1;if(ff)x=-x;return *this;}}in;struct OUT{char buf[str],*s,*t;OUT():s(buf),t(buf+str){}~OUT(){fwrite(buf,1,s-buf,stdout);}void pt(char c){(s==t)?(fwrite(s=buf,1,str,stdout),*s++=c):(*s++=c);}OUT&operator<<(const char*s){while(*s)pt(*s++);return *this;}OUT&operator<<(char*s){while(*s)pt(*s++);return *this;}OUT&operator<<(string s){for(int i=0;s[i];i++)pt(s[i]);return *this;}template<typename T>OUT&operator<<(T x){if(!x)return pt('0'),*this;if(x<0)pt('-'),x=-x;char a[30],t=0;while(x)a[t++]=x%10,x/=10;while(t--)pt(a[t]+'0');return *this;}}out;}using namespace IO;
#define N 151
#define M 511
int n,m,f[N][M];
int W[N],V[N],D[N];
int cnt=0,head[N];
struct edge{
    int to,nxt;
}e[N*2];
void add(int x,int y){
    e[++cnt].to=y;e[cnt].nxt=head[x];head[x]=cnt;
}
int dfn[N],low[N],sz=0,tp=0,st[N],bl[N],tt=0,w[N],vv[N];
bool v[N];
void tarjan(int x){
    dfn[x]=low[x]=++sz;v[x]=1;
    st[++tp]=x;
    fl(i,x)
    if(!dfn[to])tarjan(to),low[x]=MIN(low[x],low[to]);
    else if(v[to])low[x]=MIN(low[x],dfn[to]);

    if(low[x]==dfn[x]){
        ++tt;
        while(int k=st[tp--]){
            bl[k]=tt;v[k]=0;
            w[tt]+=W[k];vv[tt]+=V[k];
            if(k==x)break;
        }
    }
}
int ind[N];
void sol(int x){
    Fur(i,w[x],m)f[x][i]=vv[x];
    fl(i,x){
        sol(to);
        int k=m-w[x];
        Fdr(i,k,0)
            Fur(j,0,i)
            f[x][i+w[x]]=MAX(f[x][i+w[x]],f[to][j]+f[x][i+w[x]-j]);
    }
}
int main(){
    fin("in");
    in>>n>>m;
    Fur(i,1,n)in>>W[i];
    Fur(i,1,n)in>>V[i];
    Fur(i,1,n){
        in>>D[i];
        if(D[i])add(D[i],i);
    }
    Fur(i,1,n)if(!dfn[i])tarjan(i);
    clr(head,0);cnt=0;
    Fur(i,1,n)
    if(bl[D[i]]!=bl[i]){
        add(bl[D[i]],bl[i]);
        // out<<bl[D[i]]<<" "<<bl[i]<<ln;
        ind[bl[i]]++;
    }
    Fur(i,1,n)if(!ind[i])add(0,i);
    sol(0);
    out<<f[0][m]<<ln;
}
LG 2515 [HAOI2010]软件安装
comment评论
Search
search