ICPC2022杭州站（补题）

A-Modulo Ruins the Legend

#include<bits/stdc++.h>
#define ll long long
using namespace std;
ll n,m,sum,n1,n2;
ll Gcd(ll a,ll b)
{
    if(!b) return a;
    return Gcd(b,a%b);
}
ll Ex_gcd(ll a,ll b,ll &x,ll &y)
{
    if(!b){ x=1; y=0; return a;}
    ll d=Ex_gcd(b,a%b,x,y);
    ll t=x;
    x=y;
    y=t-(a/b)*y;
    return d;
}
int main()
{
    scanf("%lld%lld",&n,&m);
    for(int i=1;i<=n;i++)
    {
        ll t;
        scanf("%lld",&t);
        sum+=t;
    }
    sum%=m;
    n1=n; n2=n*(n+1)/2;
    ll gcd=Gcd( Gcd(n1,n2),m );
    ll ans=-(sum/gcd)*gcd+sum;
    cout<<ans<<"\n";
    ll a=Gcd(n1,n2),b=m,x,y;
    Ex_gcd(a,b,x,y);
    
    x=x*(ans-sum)/gcd;
    ll dx=b/gcd;
    x=x+ceil((-x+1)/dx)*dx;
    
    ll s,d;
    a=n1,b=n2;
    Ex_gcd(a,b,s,d);
    s=s*x;
    d=d*x;
    s=(s%m+m)%m;
    d=(d%m+m)%m;
    cout<<s<<" "<<d;
    return 0;
}

C-No Bug No Game

#include<bits/stdc++.h>
using namespace std;
int n,k,p[3005],Ans=0;
int w[3005][11],S=0;
int f[3005][3005][2];
int Work(int P)
{
    memset(f,128,sizeof(f));
    f[0][0][0]=f[0][0][1]=0;
    for(int i=1;i<=n;i++)
        for(int j=0;j<=k-P;j++)
        {
            f[i][j][0]=max(f[i][j][0],f[i-1][j][0]);
            if(j-p[i]>=0) f[i][j][0]=max(f[i][j][0],f[i-1][j-p[i]][0]+w[i][p[i]]);
            f[i][j][1]=max(f[i][j][1],f[i-1][j][1]);
            if(P<=p[i]) f[i][j][1]=max(f[i][j][1],f[i-1][j][0]+w[i][P]);
            if(j-p[i]>=0) f[i][j][1]=max(f[i][j][1],f[i-1][j-p[i]][1]+w[i][p[i]]); 
        }
    int ans=max(f[n][k-P][0],f[n][k-P][1]);
    return ans;
}
int main()
{
    scanf("%d%d",&n,&k);
    int sum=0;
    for(int i=1;i<=n;i++)
    {
        scanf("%d",p+i);
        sum+=p[i];
        for(int j=1;j<=p[i];j++) scanf("%d",&w[i][j]);
        S+=w[i][p[i]];
    } 
    if(sum<=k) 
    {
        cout<<S;
        return 0;
    }
    for(int i=0;i<=10;i++) 
    {
        int t=Work(i);
        Ans=max(Ans,t);
    }
    cout<<Ans;
    return 0;
}

D-Money Game

#include<bits/stdc++.h>
using namespace std;
int n;
double a,S,ans;
int main()
{
    scanf("%d",&n);
    for(int i=1;i<=n;i++)
    {
        scanf("%lf",&a);
        S+=a;
    }
    ans=S/double(n+1);
    printf("%.7lf ",2*ans);
    for(int i=2;i<=n;i++) printf("%.7lf ",ans);
    return 0;
}

E-Oscar is All You Need

#include<bits/stdc++.h>
using namespace std;
const int MAXN=1005;
int T;
int n,a[MAXN];
int sum,xx[MAXN*2],yy[MAXN*2];
void Swap(int x,int y,int *b)
{
    sum++;
    xx[sum]=x; yy[sum]=y;
    int tmp[MAXN]={0},num=0;
    for(int i=n-y+1;i<=n;i++) tmp[++num]=b[i];
    for(int i=x+1;i<=n-y;i++) tmp[++num]=b[i];
    for(int i=1;i<=x;i++) tmp[++num]=b[i];
    for(int i=1;i<=n;i++) b[i]=tmp[i];
}
void Work()
{
    sum=0;
    scanf("%d",&n);
    for(int i=1;i<=n;i++) scanf("%d",&a[i]);
    if(n==3)
    {
        if(a[1]>a[3]) printf("1\n1 1\n");
        else printf("0\n");
        return ;
    }
    
    int p;
    for(int i=1;i<=n;i++)
        if(a[i]==1){ p=i; break; }
    if(p==2) 
    {
        Swap(2,1,a);
        Swap(1,1,a);
    }
    else if(p>2) Swap(1,n-p+1,a);
    
    while(1)
    {
        int k=1;
        for(int i=2;i<=n;i++)
        {
            if(a[i]>a[i-1]) k++;
            else break; 
        }
        if(k==n) break;
        int j=1;
        for(int i=1;i<=k;i++)
            if(a[n]>a[i]) j=i;
        if(j<n-2)
        {
            Swap(j,2,a);
            Swap(1,j,a);
        }
        if(j==n-2)
        {
            Swap(1,1,a);
            Swap(n-2,1,a);
            Swap(2,n-3,a);
            Swap(n-3,1,a);
            Swap(1,n-2,a);
        }
    }
    cout<<sum<<"\n";
    for(int i=1;i<=sum;i++) cout<<xx[i]<<" "<<yy[i]<<"\n";
}
int main()
{
    scanf("%d",&T);
    while(T--) Work(); 
    return 0;
} 

F-Da Mi Lao Shi Ai Kan De

#include<bits/stdc++.h>
using namespace std;
int n,m;
char s[10005];
map<string,int> ma;
int main()
{
    cin>>n;
    while(n--)
    {
        int flag=0;
        cin>>m;
        while(m--)
        {
            scanf("%s",s+1);
            int len=strlen(s+1);
            if(ma[s+1]) continue;
            for(int i=3;i<=len;i++)
            {
                if(s[i-2]=='b'&&s[i-1]=='i'&&s[i]=='e')
                {
                    ma[s+1]=1;
                    printf("%s\n",s+1);
                    flag=1; break;
                }
            }
        }
        if(!flag) puts("Time to play Genshin Impact, Teacher Rice!");
    }
    return 0;
} 

G-Subgraph Isomorphism

#include<bits/stdc++.h>
#define ll long long
using namespace std;
const int MAXN=1e5+5,MAXM=1e5+5;
const ll mod=998244353;
int T;
struct Edge
{
    int nxt,to; 
}e[MAXM*2];
int cnt,h[MAXN];
void Add_edge(int x,int y)
{
    e[++cnt]=(Edge){h[x],y};
    h[x]=cnt;
}
int n,m;
int vis[MAXN];

int node;
ll f[MAXN],dep[MAXN],deg[MAXN]; 
ll trans1[MAXN],trans2[MAXN];
void Get_hash(int u,int fa)
{
    f[u]=19260817;
    dep[u]=deg[u]=1;
    vector<int> a;
    for(int i=h[u];i;i=e[i].nxt)
    {
        int v=e[i].to;
        if( v==fa || vis[v] ) continue;
        Get_hash(v,u);
        f[u]=(f[u]+f[v])%mod;
        dep[u]=max(dep[u],dep[v]+1);
        deg[u]++;
        a.push_back(v);
    }
    f[u]=f[u]*trans1[dep[u]]%mod*trans2[deg[u]]%mod;
}
int dfn[MAXN],id;
int fa[MAXN];
int c[MAXN],num=0;
void Get_loop(int u)
{
    dfn[u]=++id;
    for(int i=h[u];i;i=e[i].nxt)
    {
        int v=e[i].to;
        if(v==fa[u]) continue;
        if(dfn[v])
        {
            if(dfn[v]<dfn[u]) continue;
            c[++num]=v;
            for(;v!=u;v=fa[v]) c[++num]=fa[v];
            return ;
        }
        else fa[v]=u,Get_loop(v);
    }
}
void Clean()
{
    cnt=0; 
    for(int i=1;i<=n;i++) h[i]=0;
    for(int i=1;i<=n;i++) vis[i]=0;
    for(int i=1;i<=n;i++) dfn[i]=0;
    id=0;
    for(int i=1;i<=num;i++) c[i]=0;
    num=0;
}
ll random(ll x)
{
    return (ll)(1.0*rand()/RAND_MAX*x)+1;
}
void Work()
{
    scanf("%d%d",&n,&m);
    for(int i=1;i<=n;i++) trans1[i]=random(1e7),trans2[i]=random(1e7);
    for(int i=1;i<=m;i++)
    {
        int x,y;
        scanf("%d%d",&x,&y);
        Add_edge(x,y); Add_edge(y,x);
    }
    if(m==n-1||m>n)
    {
        cnt=0;
        for(int i=1;i<=n;i++) h[i]=0;//clean
        
        if(m==n-1){ puts("YES"); return; }
        if(m>n){ puts("NO"); return; }
    }
    
    Get_loop(1);
    for(int i=1;i<=num;i++) vis[c[i]]=1;
    for(int i=1;i<=num;i++) Get_hash(c[i],0);
    
    int flag1=1,flag2=1;
    for(int i=2;i<=num;i++)
        if( f[c[i]]!=f[c[1]]){ flag1=0; break; }
    for(int i=3;i<=num;i+=2) 
        if( f[c[i]]!=f[c[1]]){ flag2=0; break; }
    for(int i=4;i<=num;i+=2)
        if( f[c[i]]!=f[c[2]]){ flag2=0; break; }
    if( flag1 || ( flag2 && num%2==0 ) ) puts("YES");
    else puts("NO");
    
    Clean();
}
int main()
{ 
    scanf("%d",&T);
    while(T--) Work();
    return 0;
}

I-Guess Cycle Length

#include<bits/stdc++.h>
using namespace std;
const int K=3333;
int random()
{
    return (int)(1.0*rand()/RAND_MAX*1e9);
}
map<int,int> ma;
int main()
{
    srand(time(0));
    int m=0,x;
    for(int i=1;i<=K;i++)
    {
        printf("walk %d\n",random());
        fflush(stdout);
        scanf("%d",&x);
        if(x>m) m=x;
    }
    for(int i=1;i<=K;i++)
    {
        printf("walk %d\n",1);
        fflush(stdout);
        scanf("%d",&x);
        if(ma[x])
        {
            printf("guess %d",i-1);
            return 0;
        }
        else ma[x]=i;
    }
    printf("walk %d\n",m);
    fflush(stdout);
    scanf("%d",&x);
    if(ma[x])
    {
        printf("guess %d",K+m-ma[x]);
        return 0;
    }
    for(int i=1;i<=K;i++)
    {
        printf("walk %d\n",K);
        fflush(stdout);
        scanf("%d",&x);
        if(ma[x])
        {
            printf("guess %d",(i+1)*K+m-ma[x]);
            return 0;
        }
    }
    return 0;
}

K-Master of Both

#include<bits/stdc++.h>
#define ll long long
using namespace std;
int n,q;
char s[1000005];
int ch[1000005][27],tot=1;
ll cnt[1000005],w[27][27],pfx=0;
int big[27];
void Trie_insert()
{
    scanf("%s",s+1);
    int len=strlen(s+1),p=1;
    for(int i=1;i<=len;i++)
    {
        int x=s[i]-'a'+1;
        if(!ch[p][x]) ch[p][x]=++tot;
        int t=p;
        p=ch[p][x]; cnt[p]++;
        for(int j=1;j<=26;j++) 
            if(x!=j) w[j][x]+=cnt[ch[t][j]];
    }
    for(int i=1;i<=26;i++)
        if(ch[p][i]) pfx+=cnt[ch[p][i]]; 
}
int main()
{
    scanf("%d%d",&n,&q);
    for(int i=1;i<=n;i++) Trie_insert();
    while(q--)
    {
        char c[27];
        scanf("%s",c+1);
        for(int i=1;i<=26;i++) big[c[i]-'a'+1]=i;
        ll ans=0; 
        for(int i=1;i<=26;i++)
            for(int j=1;j<=26;j++)
            {
                if(big[i]>big[j]) ans+=w[i][j];
            }
        cout<<ans+pfx<<"\n";
    }
    return 0;
}

M-Please Save Pigeland

#include<bits/stdc++.h>
#define ll long long
using namespace std;
const ll MAXN=5e5+5;
const ll inf=1e18;
ll Gcd(ll x,ll y)
{
    if(!y) return x;
    return Gcd(y,x%y);
}
ll n,k,c[MAXN],Ans=inf;
ll vis[MAXN];
struct Edge
{
    ll nxt,to,w;
}e[MAXN*2];
ll cnt,h[MAXN];
void Add_edge(ll x,ll y,ll z)
{
    e[++cnt]=(Edge){h[x],y,z};
    h[x]=cnt;
}
ll sum[MAXN],num[MAXN];//the sum of vertex to u
ll f[MAXN],g[MAXN];
void Merge(ll &f1,ll &g1,ll f2,ll g2)
{
    if(f1==0&&g1==0)
    {
        f1=f2,g1=g2;
        return ;
    }
    if(f2==0&&g2==0) return ;
    if(f1>=f2)
    {
        g1=Gcd( g1 , Gcd(g2,f1-f2) );
        f1=f2;
    }
    else 
    {
        g1=Gcd( g1 , Gcd(g2,f2-f1) );
    }
}
void DFS1(ll u,ll fa)
{
    sum[u]=0;
    f[u]=g[u]=0;
    if(vis[u]) num[u]=1;
    for(ll i=h[u];i;i=e[i].nxt)
    {
        ll v=e[i].to;
        if(v==fa) continue;
        DFS1(v,u);
        num[u]+=num[v];
        sum[u]+=sum[v]+e[i].w*num[v];
                
        if(f[v]!=0) Merge(f[u],g[u],f[v]+e[i].w,g[v]);
        if(vis[v]) Merge(f[u],g[u],e[i].w,0); 
    }
}

void DFS2(ll u,ll fa,ll F,ll G,ll Sum,ll Num,ll W)
{
    ll f_new=f[u],g_new=g[u],sum_new=sum[u],num_new=num[u];

    sum_new+=Sum+W*Num;
    num_new+=Num;
    if(F!=0) Merge(f_new,g_new,F+W,G);
    if(vis[fa]) Merge(f_new,g_new,W,0);
    
    if(Gcd(f_new,g_new)!=0)
    {
        ll ans=sum_new/Gcd(f_new,g_new); 
        if(Ans>ans) Ans=ans;
    } 
    if(sum_new<Ans) Ans=sum_new;

    ll siz=0;
    vector<ll> a;
    a.push_back(0);
    vector<ll> ww;
    ww.push_back(0);
    for(ll i=h[u];i;i=e[i].nxt)
    {
        ll v=e[i].to;
        if(v==fa) continue;
        a.push_back(v);
        ww.push_back(e[i].w);
        siz++;
    }
    
    vector<ll> pre_f(siz+5); 
    vector<ll> pre_g(siz+5);
    vector<ll> bac_f(siz+5);
    vector<ll> bac_g(siz+5);
    
    for(ll i=1;i<=siz;i++)
    {
        ll v=a[i];
        ll ft=f[v]+ww[i],gt=g[v];
        if(f[v]==0) ft=gt=0;
        Merge(ft,gt,pre_f[i-1],pre_g[i-1]);
        if(vis[v]) Merge(ft,gt,ww[i],0);
        pre_f[i]=ft;
        pre_g[i]=gt;
    }
    for(ll i=siz;i>=1;i--)
    {
        ll v=a[i];
        ll ft=f[v]+ww[i],gt=g[v];
        if(f[v]==0) ft=gt=0;
        Merge(ft,gt,bac_f[i+1],bac_g[i+1]);
        if(vis[v]) Merge(ft,gt,ww[i],0);
        bac_f[i]=ft;
        bac_g[i]=gt;
    }

    for(ll i=1;i<=siz;i++)
    {
        ll v=a[i];
        ll f_tmp,g_tmp,sum_tmp,num_tmp;
        f_tmp=pre_f[i-1]; g_tmp=pre_g[i-1];
        if(F!=0) Merge(f_tmp,g_tmp,F+W,G);
        if(vis[fa]) Merge(f_tmp,g_tmp,W,0); 
        Merge(f_tmp,g_tmp,bac_f[i+1],bac_g[i+1]);
        sum_tmp=sum_new-sum[v]-num[v]*ww[i];
        num_tmp=num_new-num[v];
        
        DFS2(v,u,f_tmp,g_tmp,sum_tmp,num_tmp,ww[i]);
    }
}
int main()
{
    scanf("%lld%lld",&n,&k);
    for(ll i=1;i<=k;i++) 
        scanf("%lld",&c[i]),vis[c[i]]=1;
    for(ll i=1;i<n;i++)
    {
        ll x,y,z;
        scanf("%lld%lld%lld",&x,&y,&z);
        Add_edge(x,y,z);
        Add_edge(y,x,z);
    }
    DFS1(1,0);
    DFS2(1,0,0,0,0,0,0);
    cout<<Ans*2;
    return 0;
}