Submission #937389

#	Time	Username	Problem	Language	Result	Execution time	Memory
937389		sleepntsheep	Rigged Roads (NOI19_riggedroads)	C++17	59 / 100	353 ms	136276 KiB

riggedroads

#include<assert.h>
#include<stdio.h>
#include<stdlib.h>
#include<string.h>

unsigned X=12345;int rand_(){return(X*=3)>>1;}
int(*compar)(int,int);void sort(int*aa,int l,int r){ while(l<r){ int i=l,j=l,k=r,t,p=aa[l+rand_()%(r-l)]; while(j<k)switch(compar(aa[j],p)){case 0:++j;break;case -1:t=aa[i],aa[i]=aa[j],aa[j]=t,++i,++j;break;case 1:t=aa[--k],aa[k]=aa[j],aa[j]=t;break;}sort(aa,l,i);l=k; }}

#define N 600005
int t[N<<2], lz[N<<2];
void push(int v, int l, int r)
{
    if (~lz[v])
    {
        if (l != r) lz[2*v+1] = lz[2*v+2] = lz[v];
        t[v] = lz[v]*(r-l+1);
        lz[v] = -1;
    }
}

void upd(int v, int l, int r, int x, int y, int k)
{
    push(v, l, r);
    if (r < x||y<l)return;
    if(x<=l&&r<=y){lz[v]=k;push(v,l,r);return;}
    upd(2*v+1, l,(l+r)/2,x,y,k),upd(2*v+2,(l+r)/2+1,r,x,y,k);
    t[v]=t[2*v+1]+t[2*v+2];
}

int qry(int v,int l,int r,int x,int y)
{
    push(v,l,r);
    if(r<x||y<l)return 0;
    if(x<=l&&r<=y)return t[v];
    return qry(2*v+1,l,(l+r)/2,x,y)+qry(2*v+2, (l+r)/2+1, r, x,y);
}

int lo(int a,int b){return a<b?a:b;}

int t2[N<<2], lz2[N<<2];
void push2(int v, int l, int r)
{
    if (1e9<=lz2[v])return;
    if (l != r) lz2[2*v+1]=lo(lz2[2*v+1],lz2[v]),lz2[2*v+2]=lo(lz2[2*v+2],lz2[v]);
    t2[v] = lo(t2[v],lz2[v]);
    lz2[v] = 1e9;
}

void upd2(int v, int l, int r, int x, int y, int k)
{
    push2(v, l, r);
    if (r < x||y<l)return;
    if(x<=l&&r<=y){lz2[v]=k;push2(v,l,r);return;}
    upd2(2*v+1, l,(l+r)/2,x,y,k),upd2(2*v+2,(l+r)/2+1,r,x,y,k);
    t2[v]=lo(t2[2*v+1],t2[2*v+2]);
}

int qry2(int v,int l,int r,int x,int y)
{
    push2(v,l,r);
    if(r<x||y<l)return 1e9;
    if (x<=l&&r<=y)return t2[v];
    return lo(qry2(2*v+1,l,(l+r)/2,x,y),qry2(2*v+2, (l+r)/2+1, r, x,y));
}

int n,m,h[N],e[N<<1][2],ne=1,y[N],P[19][N],dd[N],ch[N],ci[N],timer=0,w[N],ee[N],eee[N],sz[N];
void _l(int u,int v){e[++ne][0]=v,e[ne][1]=h[u],h[u]=ne;}

void dfs(int u,int p){
    P[0][u]=p;
        for(int j=1;j<19;++j)P[j][u]=P[j-1][P[j-1][u]];
    sz[u]=1;
    for(int v,j=h[u];j;j=e[j][1])if((v=e[j][0])!=p&&y[j>>1]){
        dd[v]=dd[u]+1;
        ee[v]=j>>1;
        eee[j>>1]=v;
        dfs(v,u);
        sz[u]+=sz[v];
    }
}

void hld(int u,int hh)
{
    int hv=0;
    for(int v,j=h[u];j;j=e[j][1])if((v=e[j][0])!=P[0][u]&&y[j>>1]) if(sz[v]>sz[hv])hv=v;
    ci[u]=timer++;ch[u]=hh;
    if(hv)hld(hv,hh);
    for(int v,j=h[u];j;j=e[j][1])if((v=e[j][0])!=P[0][u]&&y[j>>1]&&v-hv) hld(v,v);
}

int qq(int u,int v){
    if(dd[u]>dd[v])return qq(v,u);
    int dt=dd[v]-dd[u];
    for(int j=19;j--;)if(dt&(1<<j))v=P[j][v];
    if(u==v)return u;
    for(int j=19;j--;)if(P[j][u]^P[j][v])u=P[j][u],v=P[j][v];
    return P[0][u];
}

int anc(int u,int d)
{
    for(int j=19;j--;)if(dd[P[j][u]]>=d)u=P[j][u];
    return u;
}

int need[N],np,ord=1;

int cup(int u,int a)
{
    int z=0;
    for(;ch[u]!=ch[a];u=P[0][ch[u]])
        z+=qry(0,0,n,ci[ch[u]],ci[u]);
    z+=qry(0,0,n,ci[a],ci[u]);
    return z;
}

void sup(int u,int a,int k)
{
    //printf(" SUP %d %d\n",u,a);
    for(;ch[u]!=ch[a];u=P[0][ch[u]])
        upd(0,0,n,ci[ch[u]],ci[u],0),
        upd2(0,0,n,ci[ch[u]],ci[u],k);
    upd(0,0,n,ci[a],ci[u],0);
    upd2(0,0,n,ci[a],ci[u],k);
}

static int use[N],at[N];

int *eh[N],eo[N];
void append(int i,int j) {
    int o=eo[i]++;
    if(o>=2&&(o&(o-1))==0)eh[i]=(int*)realloc(eh[i],2*o*sizeof**eh);
    eh[i][o]=j;
}

int main(){
    memset(lz,-1,sizeof lz);
    memset(lz2,63,sizeof lz2);
    memset(t2,63,sizeof t2);

    scanf("%d%d",&n,&m);
    for(int u,v,i=1;i<=m;++i)scanf("%d%d",&u,&v),_l(u,v),_l(v,u);
    for(int j,i=1;i<n;++i)scanf("%d",&j),y[j]=1;
    dfs(1,1);hld(1,1);

    upd(0,0,n,0,n,1);
    upd(0,0,n,ci[1],ci[1],0);
    upd2(0,0,n,0,n,1e8);

    for(int j=1;j<=m;++j){
        int u=e[j*2][0],v=e[j*2+1][0];
        if(dd[v]+1==dd[u]){int t=u;u=v;v=t;}
        if(!y[j]){
            int lca=qq(u,v),uk=anc(u,dd[lca]+1),vk=anc(v,dd[lca]+1);
            //printf(" : %d %d %d %d %d\n",u,v,lca,uk,vk);

            if(u-lca)ord+=cup(u,uk),sup(u,uk,j);
            if(v-lca)ord+=cup(v,vk),sup(v,vk,j);

            use[w[j]=ord++]=1;
        }else {
            if(qry(0,0,n,ci[v],ci[v])){
                use[w[j]=ord++]=1;
                assert(dd[u]+1==dd[v]);
                upd(0,0,n,ci[v],ci[v],0);
            }
        }
    }

    for(int i=0;i<=n+1;++i)eh[i]=(int*)malloc(2*sizeof**eh);
    for(int j=1;j<=m;++j){
        if(!w[j])
        {
            int u=eee[j];
            at[j]=qry2(0,0,n,ci[u],ci[u]);
            if(at[j]>n+1)at[j]=n+1;
            //printf(" : %d %d %d\n",j,u,at[j]);
            append(at[j],j);
        }
    }

    int ord2=1;
    for(int j=0;j<=n+1;++j){
        for(int i=0;i<eo[j];++i){
            while(use[ord2])++ord2;
            w[eh[j][i]]=ord2++;
        }
        //printf(" : %d %d\n",at[ww[j]],ww[j]);
    }

    for(int j=1;j<=m;++j)printf("%d ",w[j]);
}

Compilation message (stderr)

riggedroads.cpp: In function 'int main()':
riggedroads.cpp:142:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
  142 |     scanf("%d%d",&n,&m);
      |     ~~~~~^~~~~~~~~~~~~~
riggedroads.cpp:143:35: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
  143 |     for(int u,v,i=1;i<=m;++i)scanf("%d%d",&u,&v),_l(u,v),_l(v,u);
      |                              ~~~~~^~~~~~~~~~~~~~
riggedroads.cpp:144:32: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
  144 |     for(int j,i=1;i<n;++i)scanf("%d",&j),y[j]=1;
      |                           ~~~~~^~~~~~~~~

• Subtask 1: 8 / 8
• Subtask 2: 19 / 19
• Subtask 3: 0 / 9
• Subtask 4: 10 / 10
• Subtask 5: 10 / 10
• Subtask 6: 12 / 12
• Subtask 7: 0 / 32