Submission #573292

#	Time	Username	Problem	Language	Result	Execution time	Memory
573292		MohamedAliSaidane	Stranded Far From Home (BOI22_island)	C++14	10 / 100	1093 ms	16332 KiB

island

#include<bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>

        using namespace __gnu_pbds;
        using namespace std;

        typedef tree<int,null_type,less<int>,rb_tree_tag,
        tree_order_statistics_node_update> indexed_set;

        typedef long long ll;
        typedef long double ld;

        typedef pair<int,int> pii;
        typedef pair<ll,ll> pll;
        typedef pair<ld,ld> pld;

        typedef vector<int> vi;
        typedef vector<ll> vll;
        typedef vector<pii> vpi;
        typedef vector<pll> vpl;

        #define pb push_back
        #define popb pop_back
        #define pp pop_back
        #define pf push_front
        #define popf pop_front
        #define all(x) (x).begin(),(x).end()
        #define ff first
        #define ss second

        ///#define int ll

        int nx[4] = {0,0,1,-1}, ny[4] = {1,-1,0,0};
        ll gcd(ll a , ll b) {return b ? gcd(b , a % b) : a ;}
        ll lcm(ll a , ll b) {return (a * b) / gcd(a , b);}

        const int nax = 2e5 + 4;
        int n, m;
        ll s[nax];
        vi adj[nax];
        ll pref[nax];
        void sub1()
        {
            string ans = "";
            for(int i = 1; i<= n; i++)
                ans += '1';
            ll sum = 0ll;
            for(int i  = 1 ; i <= n ;i ++ )
                sum += s[i];
            for(int i = 1; i <= n; i++)
            {
                ll cur = s[i];
                set<pll> pq;
                for(auto e: adj[i])
                    pq.insert({s[e],e});
                bool vis[n + 1];
                memset(vis,false,sizeof(vis));
                vis[i] = 1;
                while(!pq.empty())
                {
                    pll u = *(pq.begin());
                    pq.erase(pq.begin());
                    if(u.ff > cur)
                    {
                        ans[i - 1] = '0';
                        vis[u.ss] = 0;
                        break;
                    }
                    cur += u.ff;
                    vis[u.ss] = 1;
                    for(auto e: adj[u.ss])
                    {
                        if(vis[e])
                            continue;
                        vis[e]  = 1;
                        pq.insert({s[e],e});
                    }
                }
                if(cur < sum)
                    ans[ i - 1] - '0';
            }
            cout << ans;
        }
        void solve()
        {
            cin >> n >> m;
            for(int i = 1; i <= n; i++)
                cin >> s[i];
            for(int i = 1; i <= m; i ++)
            {
                int a, b;
                cin >> a >> b;
                adj[a].pb(b);
                adj[b].pb(a);
            }
            if(n <= 2000 && m <= 2000)
            {
                sub1();
                return ;
            }

            for(int i = 1;i  <= n ;i++)
                pref[i] = pref[i - 1] + s[i];
            int mint[n + 1];
            int maxt[n + 1];
            string ans = "";
            for(int i = 1; i <= n; i++)
            {
                mint[i] = maxt[i] = i;
                ans += '1';
            }

            for(int node = 1; node <= n; node++)
            {
                ll cur = s[node];
                int i = node - 1, j= node + 1;
                //cout << node << endl;
                while(i > 0 || j <= n)
                {
                    cur = pref[j] - pref[i];
                    j = max(j,maxt[i + 1] + 1);
                    //cout << node << ' ' << i << ' ' << j << endl;
                    if(i >= 1)
                    {
                        //cout << i << endl;
                        if(s[i] <= cur)
                        {
                            maxt[i] = max(maxt[i],j - 1);
                            mint[j - 1] = min(mint[j - 1],i);

                            i --;
                            continue;
                        }
                    }
                    if(j <= n)
                    {
                        //cout << j << endl;
                        if(s[j] <= cur)
                        {
                            maxt[i + 1] = max(maxt[i +1],j);
                            mint[j] = min(mint[j],i + 1);
                            j ++;
                            continue;
                        }
                    }
                    break;
                }
                //cout << node << ' ' << i << ' ' << j << endl;
                ans[node - 1] = (char)((int)('0') + (i == 0 && j == n + 1));
            }
            cout << ans;
        }

        int32_t main()
        {
            ios::sync_with_stdio(false);
            cin.tie(0); cout.tie(0);
            int tt = 1;
            while(tt --)
                solve();
        }

Compilation message (stderr)

island.cpp: In function 'void sub1()':
island.cpp:80:33: warning: value computed is not used [-Wunused-value]
   80 |                     ans[ i - 1] - '0';

• Subtask 1: 10 / 10
• Subtask 2: 0 / 10
• Subtask 3: 0 / 15
• Subtask 4: 0 / 30
• Subtask 5: 0 / 35