Submission #598483

#	Time	Username	Problem	Language	Result	Execution time	Memory
598483		urosk	Paths (BOI18_paths)	C++14	100 / 100	704 ms	47484 KiB

paths

#define here cerr<<"===========================================\n"
#include <bits/stdc++.h>
#define ld double
#define ll long long
#define llinf 100000000000000000LL // 10^17
#define pb push_back
#define popb pop_back
#define fi first
#define sc second
#define endl '\n'
#define pll pair<ll,ll>
#define pld pair<ld,ld>
#define sz(a) (ll)(a.size())
#define all(a) a.begin(),a.end()
#define ceri(a,l,r) {for(ll i_ = l;i_<=r;i_++) cerr<<a[i_]<< " ";cerr<<endl;}
#define daj_mi_malo_vremena ios_base::sync_with_stdio(false);cerr.tie(0);cout.tie(0);cin.tie(0);

using namespace std;
#define maxn 300005
#define maxk 6
ll n,m,k;
ll ans = 0;
vector<ll> g[maxn];
ll a[maxn];
ll dp[maxn][maxk][maxk];
ll cnt[maxn][maxk];
vector<pll> edg;
void kraj(){
    cout<<ans<<endl;
    exit(0);
}
pll fale(vector<ll> v){
    vector<bool> tu(k+1);
    for(ll x : v) tu[x] = 1;
    pll p = {-1,-1};
    for(ll i = 1;i<=k;i++){
        if(!tu[i]){
            if(p.fi==-1) p.fi = i;
            else p.sc = i;
        }
    }
    return p;
}
int main(){
	daj_mi_malo_vremena
    cin >> n >> m >> k;
    for(ll i = 1;i<=n;i++) cin >> a[i];
    for(ll i = 1;i<=m;i++){
        ll x,y; cin >> x >> y;
        edg.pb({x,y});
        g[x].pb(y);
        g[y].pb(x);
    }
    if(k==1) kraj();
    ll cur = 0;
    for(ll i = 1;i<=n;i++){
        for(ll j : g[i]){
            if(a[i]==a[j]) continue;
            cnt[i][a[j]]++;
            cur++;
        }
    }
    ans+=cur;
    if(k==2) kraj();
    cur = 0;
    for(ll i = 1;i<=n;i++){
        vector<ll> v(k+1);
        for(ll j : g[i]){
            v[a[j]]++;
        }
        ll coli = a[i];
        for(ll e = 1;e<=k;e++){
            for(ll r = e+1;r<=k;r++){
                if(e==coli||r==coli) continue;
                cur+=v[e]*v[r];
            }
        }
    }
    ans+=2*cur;
    cerr<<"k = 3: "<<ans<<endl;
    if(k==3) kraj();
    cur = 0;
    for(pll p : edg){
        ll x = p.fi;
        ll y = p.sc;
        ll colx = a[x];
        ll coly = a[y];
        if(colx==coly) continue;
        for(ll e = 1;e<=k;e++){
            if(e==colx||e==coly) continue;
            for(ll r = e+1;r<=k;r++){
                if(r==colx||r==coly) continue;
                cur+=cnt[x][e]*cnt[y][r];
                cur+=cnt[x][r]*cnt[y][e];
            }
        }
    }
    cur*=2;
    ans+=cur;
    if(k==4) kraj();
    for(ll i = 1;i<=n;i++){
        for(ll j : g[i]){
            ll coli = a[i];
            ll colj = a[j];
            for(ll e = 1;e<=k;e++){
                dp[i][colj][e] += cnt[j][e];
                if(e==coli) dp[i][colj][e]--;
            }
        }
    }
    cur = 0;
    for(ll i = 1;i<=n;i++){
        ll coli = a[i];
        for(ll e = 1;e<=k;e++){
            for(ll r = 1;r<=k;r++){
                pll p = fale({coli,e,r});
                ll f = p.fi;
                ll g = p.sc;
                set<ll> s;
                s.insert(coli);
                s.insert(r);
                s.insert(e);
                s.insert(g);
                s.insert(f);
                if(sz(s)!=5) continue;
                cur+=dp[i][e][r]*dp[i][f][g];
                cur+=dp[i][e][r]*dp[i][g][f];
            }
        }
    }
    ans+=cur;
    if(k==5) kraj();
	return 0;
}
/*
4 3 3
1 2 1 3
1 2
2 3
4 2

9 11 4
1 2 3 4 1 2 1 2 2
1 2
1 3
2 3
2 4
3 6
6 2
6 5
4 3
4 5
7 8
9 8
*/

• Subtask 1: 23 / 23
• Subtask 2: 20 / 20
• Subtask 3: 27 / 27
• Subtask 4: 30 / 30