Submission #1185742

#	Time	Username	Problem	Language	Result	Execution time	Memory
1185742		asli_bg	Šarenlist (COCI22_sarenlist)	C++20	10 / 110	0 ms	400 KiB

Main

#include <bits/stdc++.h>
using namespace std;

#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;

#define int long long

typedef pair<int,int> pii;
typedef vector<int> vi;
typedef vector<pii> vii;
typedef vector<bool> vb;

typedef tree<pii,null_type,less<pii>,rb_tree_tag,
tree_order_statistics_node_update> oset;

#define fi first
#define se second
#define pb push_back

#define mid (l+r)/2
#define all(x) x.begin(),x.end()
#define FOR(i,a) for(int i=0;i<(a);i++)
#define FORE(i,a,b) for(int i=(a);i<(b);i++)

#define cont(x) for(auto el:x) cout<<el<<' ';cout<<endl;
#define contp(x) for(auto el:x) cout<<el.fi<<'-'<<el.se<<' ';cout<<endl;
#define sp <<" "<<

#define DEBUG(x) cout<<(#x) sp x<<endl
#define carp(a,b) (((a%MOD)*(b%MOD))%MOD)
#define topla(a,b) (((a%MOD)+(b%MOD))%MOD)

const int INF=1e18;
const int MAXN=65;
const int MAXK=10;
const int MOD=1e9+7;

int n,m,k;

vii adj[MAXN];
int up[MAXN][MAXK];

int dep[MAXN];
pii p[MAXN];

void dfs(int nd,int ata,int h){
    dep[nd]=h;
    for(auto [kom,ind]:adj[nd]){
        if(kom==ata) continue;
        p[kom]={nd,ind};
        dfs(kom,nd,h+1);
    }
}

void calc(){
    memset(up,-1,sizeof up);
    FORE(i,1,n+1){
        up[i][0]=p[i].fi;
    }

    FORE(j,1,MAXK){
        FORE(i,1,n+1){
            if(up[i][j-1]==-1) continue;
            up[i][j]=up[up[i][j-1]][j-1];
        }
    }
}

int lca(int a,int b){
    //a altta olan, b üstte olan
    if(dep[a]<dep[b]) swap(a,b);
    for(int i=MAXK-1;i>=0;i--){
        int tt=up[a][i];
        if(tt==-1) continue;
        if(dep[tt]>=dep[b]) a=tt;
    }

    if(a==b) return a;

    for(int i=MAXK-1;i>=0;i--){
        int bir=up[a][i];
        int iki=up[b][i];

        if(bir==-1 or iki==-1) continue;
        if(bir!=iki){
            a=bir;
            b=iki;
        }
    }

    return up[a][0];
}

int exp(int x,int us){
    int res=1;
    while(us>0){
        if(us&1) res=carp(res,x);
        x=carp(x,x);
        us/=2;
    }
    return res;
}

int comp;
bool used[MAXN], vis[MAXN];

void dfs2(int nd,int ata){
    vis[nd]=true;
    for(auto [kom,ind]:adj[nd]){
        if(kom==ata or !used[ind]) continue;
        dfs2(kom,nd);
    }
}

signed main(){
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);

    cin>>n>>m>>k;

    FOR(i,n-1){
        int a,b;
        cin>>a>>b;
        adj[a].pb({b,i});
        adj[b].pb({a,i});
    }

    p[1]={-1,-1};
    dfs(1,-1,0);

    calc();

    vector<pair<pii,int>> tut;

    FOR(i,m){
        int a,b;
        cin>>a>>b;
        if(dep[a]<dep[b]) swap(a,b); //a altta olan
        tut.pb({{a,b},lca(a,b)});
    }

    int ans=exp(k,n-1);

    for(int i=1;i<(1<<m);i++){
        int say=0;

        FORE(j,1,n+1){
            vis[j]=false;
            used[j-1]=false;
        }

        for(int bt=0;bt<m;bt++){
            if(i&(1<<bt)){
                int ata=tut[bt].se;

                int x=tut[bt].fi.fi;
                while(x!=ata){
                    used[p[x].se]=true;
                    x=p[x].fi;
                }

                x=tut[bt].fi.se;
                while(x!=ata){
                    used[p[x].se]=true;
                    x=p[x].fi;
                }
                say++;
            }
        }

        comp=0;
        FORE(j,1,n+1){
            if(!vis[j]){
                comp++;
                dfs2(j,-1);
            }
        }

        int deg=exp(k,comp);

        if(say%2==0) ans=topla(ans,deg);
        else ans=topla(ans,MOD-deg);
    }

    cout<<ans<<endl;
}

• Subtask 1: 10 / 10
• Subtask 2: 0 / 15
• Subtask 3: 0 / 10
• Subtask 4: 0 / 10
• Subtask 5: 0 / 65