Submission #1249384

#	Time	Username	Problem	Language	Result	Execution time	Memory
1249384		corvus	Paths (BOI18_paths)	C++20	0 / 100	31 ms	11072 KiB

paths

#include <bits/stdc++.h>
using namespace std;
 
#define all(c) begin(c), end(c)
#define pb push_back
using ll = long long;
const ll N = 3e5 + 100 , LOG = 27;

int k , n , m ; 
vector <int> color , edj[N];
set <string> res;

char get(int c) {
    return char(c + '0');
}

void dfs(int node , vector <bool> vis , string s) {
    if(vis[color[node]]) return;
    vis[color[node]] = 1;
    s.pb(get(node));
    if(s.size() > 1)
        res.insert(s);
    for(auto to : edj[node]) 
        dfs(to , vis , s);
    s.pop_back();
    vis[color[node]] = 0;
}

int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(nullptr);
    ll tt = 1;
    // cin >> tt; 
    while(tt--){
        cin >> n >> m >> k ;
        color.assign(n + 1 , {});
        for(int i = 1 ; i <= n ; i ++) cin >> color[i];
        for(int i = 0 ; i < m ; i ++) {
            int u , v ; cin >> u >> v;
            edj[u].pb(v); edj[v].pb(u);
        }
        long long res = 0 ;
        if(k >= 2) {
            res = m * 2;
            for(int i = 1 ; i <= n ; i ++)
                for(auto to : edj[i]) res -= (to == i);
        }
        if(k >= 3) {
            res += (m - 1)*2;
            for(int i = 1 ; i <= n ; i ++) {
                long long cnt[k + 1] = {};
                for(auto to : edj[i]) {
                    cnt[to] ++ ;
                }
                for(int i = 1 ; i <= k ; i ++) res -= ((cnt[i] * (cnt[i] - 1)) / 2);
            }
        }
        cout << res << '\n';
    }
    return 0;
}

• Subtask 1: 0 / 23
• Subtask 2: 0 / 20
• Subtask 3: 0 / 27
• Subtask 4: 0 / 30