oj.uz

Submission #720251

# Submission time Handle Problem Language Result Execution time Memory
720251 2023-04-07T18:08:36 Z jcelin Islands (IOI08_islands) C++14
46 / 100
 1000 ms 131072 KB 
#include <bits/stdc++.h>
using namespace std;

typedef long long ll;

#define vll vector<ll>
#define PB push_back
#define FOR(i, a, b) for (int i = int(a); i < int(b); i++)
#define REP(i, n) FOR(i, 0, n)
#define all(x) (x).begin(), (x).end()

const ll INF = (1 << 58);
const int MAXN = 1e6 + 7;

bool bio[MAXN];
int to[MAXN], w[MAXN]; 
vector<int> g[MAXN];
ll ans, ret;
vll dp, s;

int ciklus(int u){
	if(bio[u]) return u;
	bio[u] = 1;
	int v = ciklus(to[u]);
	if(v){
		dp.PB(u);
		s.PB(w[u]);
		if(u == v) return 0;
		return v;
	}
	bio[u] = 0;
	return 0;
}

ll dfs(int u){
	ll mx = 0;
	bio[u] = 1;
	for(int &x : g[u]){
		if(bio[x]) continue;
		ll ch = w[x] + dfs(x);
		ret = max(ret, (ll)ch + (ll)mx);
		mx = max(mx, ch);
	}
	return mx;
}

void resi(int u){
	dp.clear(), s.clear();
	ciklus(u);
	int sz = s.size();
	reverse(all(dp));
	reverse(all(s));
	for(ll &x : dp) x = (ll)dfs(x);
	for(int i = sz - 1; i; i--) swap(s[i], s[i - 1]);
	FOR(i, 1, sz) s[i] += s[i - 1];
	ll m1 = -INF, m2 = -INF;
	REP(i, sz){
		ret = max(ret, (ll)dp[i] + (ll)s[i] + (ll)m1);
		ret = max(ret, (ll)s[sz - 1] + (ll)m2 + (ll)dp[i] - (ll)s[i]);
		m1 = max(m1, (ll)dp[i] - (ll)s[i]);
		m2 = max(m2, (ll)dp[i] + (ll)s[i]);
	}
}

void solve(){
	int n;
	cin >> n;
	FOR(i, 1, n + 1) cin >> to[i] >> w[i], g[to[i]].PB(i); 
	FOR(i, 1, n + 1) if(!bio[i]) ret = 0, resi(i), ans += ret;
	cout << ans << "\n";
}


int main(){
	//ios_base::sync_with_stdio(false);
	//cin.tie(NULL);
	//cout.tie(NULL);
	int t=1;
	//cin >> t;
	while(t--)solve();
	return 0;
}

Compilation message

islands.cpp:12:19: warning: left shift count >= width of type [-Wshift-count-overflow]
   12 | const ll INF = (1 << 58);
      |                 ~~^~~~~

Subtask #1
6.0 / 33.0

# Verdict Execution time Memory Grader output
1 Incorrect 13 ms 23764 KB Output isn't correct
2 Correct 12 ms 23764 KB Output is correct
3 Incorrect 13 ms 23788 KB Output isn't correct
4 Incorrect 13 ms 23772 KB Output isn't correct
5 Incorrect 12 ms 23764 KB Output isn't correct
6 Incorrect 13 ms 23764 KB Output isn't correct
7 Incorrect 13 ms 23856 KB Output isn't correct
8 Incorrect 12 ms 23728 KB Output isn't correct
9 Incorrect 15 ms 23764 KB Output isn't correct
10 Correct 13 ms 23764 KB Output is correct
11 Incorrect 14 ms 23764 KB Output isn't correct

Subtask #2
0 / 3.0

# Verdict Execution time Memory Grader output
1 Correct 13 ms 23764 KB Output is correct
2 Incorrect 16 ms 23824 KB Output isn't correct
3 Halted 0 ms 0 KB -

Subtask #3
0 / 4.0

# Verdict Execution time Memory Grader output
1 Incorrect 14 ms 23812 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #4
0 / 10.0

# Verdict Execution time Memory Grader output
1 Incorrect 21 ms 24404 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #5
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 52 ms 26736 KB Output is correct
2 Correct 79 ms 28308 KB Output is correct

Subtask #6
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 152 ms 30704 KB Output is correct
2 Correct 146 ms 38684 KB Output is correct
3 Correct 206 ms 43368 KB Output is correct

Subtask #7
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 277 ms 37092 KB Output is correct
2 Correct 315 ms 51816 KB Output is correct
3 Correct 351 ms 67948 KB Output is correct
4 Correct 470 ms 72376 KB Output is correct

Subtask #8
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 659 ms 36512 KB Output is correct
2 Correct 943 ms 88132 KB Output is correct
3 Correct 566 ms 47012 KB Output is correct
4 Correct 692 ms 75184 KB Output is correct
5 Correct 650 ms 73104 KB Output is correct
6 Correct 1000 ms 51444 KB Output is correct
7 Correct 737 ms 100496 KB Output is correct

Subtask #9
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 801 ms 131072 KB Output is correct
2 Correct 731 ms 95236 KB Output is correct
3 Runtime error 728 ms 131072 KB Execution killed with signal 9
4 Halted 0 ms 0 KB -