oj.uz

Submission #530399

# Submission time Handle Problem Language Result Execution time Memory
530399 2022-02-25T09:41:24 Z fatemetmhr Love Polygon (BOI18_polygon) C++17
100 / 100
 350 ms 30020 KB 
#include <bits/stdc++.h>

using namespace std;

typedef long long ll;


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

const int maxn5 = 3e5 + 10;

int a[maxn5], req[maxn5];

int dp[2][maxn5]; // dp[0 -> khodesh nabashad/ 1 -> bashad][v]
int pd[maxn5], num[maxn5];
int sz[maxn5], parof[maxn5];
map <string, int> av;
bool mark[maxn5], incy[maxn5];
vector <int> adj[maxn5], ver, tmp;
int nn = 0, cmp[maxn5];

inline int dfs2(int v){
	//cout << "hello " << v << endl;
	mark[v] = true;
	int cy = -1;
	int u = parof[v];
	cmp[v] = nn;
	//cout << "ok " << v << ' ' << u << endl;
	if(!mark[u]){
		int z = dfs2(u);
		//cout << "aha " << z << endl;
		if(cy == -1)
			cy = z;
	}
	else if(cmp[u] == cmp[v]){
		cy = u;
	}
	//cout << ' ' << v << ' ' << cy << endl;
	if(cy != -1)
		incy[v] = true;
	return (cy == v ? -1 : cy);
}

inline void dfs(int v){
	//cout << "hello " << v << endl;
	dp[0][v] = 0;
	sz[v] = 1;
	bool re = false;
	for(auto u : adj[v]) if(!incy[u]){
		dfs(u);
		sz[v] += sz[u];
		dp[0][v] += dp[1][u] + (sz[u] % 2);
		re = true;
	}
	if(!re){
		dp[1][v] = 0;
		return;
	}
	dp[1][v] = maxn5;
	for(auto u : adj[v]) if(!incy[u]){
		int val = dp[0][v] - dp[1][u] - (sz[u] % 2);
		val += dp[0][u] + (sz[u] % 2 == 0);
		val++;
		if(sz[v] % 2 == 1)
			val--;
		dp[1][v] = min(dp[1][v], val);
	}
	if(sz[v] % 2 == 0){
		dp[0][v]--;
	}
	else{
		dp[1][v] = min(dp[1][v], dp[0][v]);
	}
	//cout << v << ' ' << dp[0][v] << ' ' << dp[1][v] << endl;
	return;
}

inline int find_next(int v){
	return parof[v];
}

int main(){
	ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
	
	int n; cin >> n;
	int ind = 0;
	for(int i = 0; i < n; i++){
		string s, t; cin >> s >> t;
		if(av.find(s) == av.end())
			av[s] = ind++;
		if(av.find(t) == av.end())
			av[t] = ind++;
		adj[av[t]].pb(av[s]);
		parof[av[s]] = av[t];
	}
	/*
	for(auto it = av.begin(); it != av.end(); it++)
		cout << "* " << (it -> fi) << ' ' << (it -> se) << endl;
	//*/
	if(n % 2 == 1)
		return cout << -1 << endl, 0;
	memset(mark, false, sizeof mark);
	for(int i = 0; i < n; i++) if(!mark[i]){
		dfs2(i);
		nn++;
	}
	for(int i = 0; i < n; i++) if(incy[i]){
		dfs(i);
	}
	//cout << "omg " << dp[1][3] << endl;
	memset(mark, false, sizeof mark);
	ll ans = 0;
	for(int i = 0; i < n; i++) if(incy[i] && !mark[i]){
		//cout << "oh a new day! " << i << endl;
		ver.clear();
		int v = find_next(i);
		mark[i] = true;
		ver.pb(i);
		while(v != i){
			mark[v] = true;
			ver.pb(v);
			//cout << v << ' ' << i << endl;
			v = find_next(v);
		}
		if(ver.size() == 1){
			ans += dp[1][i];
			if(sz[i] % 2 == 1)
				ans++;
			continue;
		}
		pd[0] = dp[1][i];
		num[0] = sz[i];
		for(int j = 1; j < ver.size(); j++){
			int u = ver[j];
			num[j] = num[j - 1] + sz[u];
			pd[j] = pd[j - 1] + dp[1][u] + 2 * (num[j - 1] % 2 == 1 && sz[u] % 2 == 1);
			int val = (j == 1 ? 0 : pd[j - 2]) + dp[0][u] + dp[0][ver[j - 1]] + 1;
			int f = (sz[u] % 2 == 0) + (sz[ver[j - 1]] % 2 == 0) + (j > 1 && num[j - 2] % 2 == 1);
			if(f >= 2)
				val += 2;
			pd[j] = min(pd[j], val);
			val = pd[j - 1] + dp[0][u] + 2 * (num[j - 1] % 2 == 1 && sz[u] % 2 == 0);
			if(num[j] % 2 == 1)
				pd[j] = min(pd[j], val);
		}
		int cur = pd[ver.size() - 1] + (num[ver.size() - 1] % 2);
		//cout << "hmm " << cur << endl;
		tmp.clear();
		tmp.pb(ver.back());
		for(auto u : ver)
			tmp.pb(u);
		tmp.pop_back();
		ver.clear();
		for(auto u : tmp)
			ver.pb(u);
		pd[0] = dp[1][ver[0]];
		num[0] = sz[ver[0]];
		//cout << "well " << pd[0] << endl;
		for(int j = 1; j < ver.size(); j++){
			int u = ver[j];
			num[j] = num[j - 1] + sz[u];
			pd[j] = pd[j - 1] + dp[1][u] + 2 * (num[j - 1] % 2 == 1 && sz[u] % 2 == 1);
			//cout << "here tar " << pd[j] << ' ' << dp[1][u] << endl;
			int val = (j == 1 ? 0 : pd[j - 2]) + dp[0][u] + dp[0][ver[j - 1]] + 1;
			int f = (sz[u] % 2 == 0) + (sz[ver[j - 1]] % 2 == 0) + (j > 1 && num[j - 2] % 2 == 1);
			if(f >= 2)
				val += 2;
			//cout << "here " << pd[j] << endl;
			pd[j] = min(pd[j], val);
			val = pd[j - 1] + dp[0][u] + 2 * (num[j - 1] % 2 == 1 && sz[u] % 2 == 0);
			if(num[j] % 2 == 1)
				pd[j] = min(pd[j], val);
			//cout << j << ' ' << ver[j] << ' ' << pd[j] << ' ' << num[j] << ' ' << sz[u] << endl;
		}
		cur = min(cur, pd[ver.size() - 1] + (num[ver.size() - 1] % 2));
		//cout << "ok " << cur << endl;
		if(ver.size() == 2){
			cur = min(cur, dp[0][ver[0]] + dp[0][ver[1]] + (sz[ver[0]] % 2 == 0) + (sz[ver[1]] % 2 == 0));
		}
		ans += cur;
	}

	cout << ans << endl;
}

/*
6
0 2
1 5
2 5
3 5
4 1
5 1
*/

Compilation message

polygon.cpp: In function 'int main()':
polygon.cpp:135:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  135 |   for(int j = 1; j < ver.size(); j++){
      |                  ~~^~~~~~~~~~~~
polygon.cpp:161:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  161 |   for(int j = 1; j < ver.size(); j++){
      |                  ~~^~~~~~~~~~~~

Subtask #1
21.0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 7628 KB Output is correct
2 Correct 4 ms 7628 KB Output is correct
3 Correct 4 ms 7628 KB Output is correct
4 Correct 4 ms 7628 KB Output is correct
5 Correct 4 ms 7372 KB Output is correct
6 Correct 4 ms 7316 KB Output is correct
7 Correct 4 ms 7628 KB Output is correct
8 Correct 6 ms 7628 KB Output is correct
9 Correct 4 ms 7628 KB Output is correct
10 Correct 5 ms 7628 KB Output is correct
11 Correct 4 ms 7628 KB Output is correct
12 Correct 4 ms 7628 KB Output is correct
13 Correct 4 ms 7628 KB Output is correct
14 Correct 4 ms 7628 KB Output is correct
15 Correct 4 ms 7628 KB Output is correct

Subtask #2
25.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 7628 KB Output is correct
2 Correct 5 ms 7628 KB Output is correct
3 Correct 4 ms 7628 KB Output is correct
4 Correct 254 ms 24192 KB Output is correct
5 Correct 302 ms 20680 KB Output is correct
6 Correct 241 ms 24636 KB Output is correct
7 Correct 280 ms 18652 KB Output is correct

Subtask #3
29.0 / 29.0

# Verdict Execution time Memory Grader output
1 Correct 242 ms 19808 KB Output is correct
2 Correct 261 ms 21832 KB Output is correct
3 Correct 211 ms 20636 KB Output is correct
4 Correct 216 ms 17096 KB Output is correct
5 Correct 253 ms 27744 KB Output is correct
6 Correct 240 ms 19140 KB Output is correct
7 Correct 233 ms 19140 KB Output is correct
8 Correct 243 ms 19396 KB Output is correct
9 Correct 220 ms 18592 KB Output is correct
10 Correct 159 ms 17848 KB Output is correct
11 Correct 5 ms 7664 KB Output is correct
12 Correct 5 ms 7628 KB Output is correct
13 Correct 5 ms 7640 KB Output is correct
14 Correct 5 ms 7628 KB Output is correct

Subtask #4
25.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 7628 KB Output is correct
2 Correct 4 ms 7628 KB Output is correct
3 Correct 4 ms 7628 KB Output is correct
4 Correct 4 ms 7628 KB Output is correct
5 Correct 4 ms 7372 KB Output is correct
6 Correct 4 ms 7316 KB Output is correct
7 Correct 4 ms 7628 KB Output is correct
8 Correct 6 ms 7628 KB Output is correct
9 Correct 4 ms 7628 KB Output is correct
10 Correct 5 ms 7628 KB Output is correct
11 Correct 4 ms 7628 KB Output is correct
12 Correct 4 ms 7628 KB Output is correct
13 Correct 4 ms 7628 KB Output is correct
14 Correct 4 ms 7628 KB Output is correct
15 Correct 4 ms 7628 KB Output is correct
16 Correct 4 ms 7628 KB Output is correct
17 Correct 5 ms 7628 KB Output is correct
18 Correct 4 ms 7628 KB Output is correct
19 Correct 254 ms 24192 KB Output is correct
20 Correct 302 ms 20680 KB Output is correct
21 Correct 241 ms 24636 KB Output is correct
22 Correct 280 ms 18652 KB Output is correct
23 Correct 242 ms 19808 KB Output is correct
24 Correct 261 ms 21832 KB Output is correct
25 Correct 211 ms 20636 KB Output is correct
26 Correct 216 ms 17096 KB Output is correct
27 Correct 253 ms 27744 KB Output is correct
28 Correct 240 ms 19140 KB Output is correct
29 Correct 233 ms 19140 KB Output is correct
30 Correct 243 ms 19396 KB Output is correct
31 Correct 220 ms 18592 KB Output is correct
32 Correct 159 ms 17848 KB Output is correct
33 Correct 5 ms 7664 KB Output is correct
34 Correct 5 ms 7628 KB Output is correct
35 Correct 5 ms 7640 KB Output is correct
36 Correct 5 ms 7628 KB Output is correct
37 Correct 260 ms 22604 KB Output is correct
38 Correct 350 ms 22112 KB Output is correct
39 Correct 253 ms 21340 KB Output is correct
40 Correct 238 ms 21316 KB Output is correct
41 Correct 236 ms 21188 KB Output is correct
42 Correct 270 ms 21864 KB Output is correct
43 Correct 237 ms 21704 KB Output is correct
44 Correct 243 ms 21748 KB Output is correct
45 Correct 264 ms 21676 KB Output is correct
46 Correct 241 ms 21652 KB Output is correct
47 Correct 237 ms 20856 KB Output is correct
48 Correct 240 ms 21948 KB Output is correct
49 Correct 268 ms 23988 KB Output is correct
50 Correct 208 ms 22724 KB Output is correct
51 Correct 227 ms 19268 KB Output is correct
52 Correct 280 ms 30020 KB Output is correct
53 Correct 234 ms 21184 KB Output is correct
54 Correct 245 ms 21232 KB Output is correct
55 Correct 245 ms 21772 KB Output is correct
56 Correct 223 ms 20644 KB Output is correct
57 Correct 159 ms 19928 KB Output is correct
58 Correct 4 ms 7628 KB Output is correct
59 Correct 4 ms 7628 KB Output is correct
60 Correct 5 ms 7628 KB Output is correct
61 Correct 4 ms 7628 KB Output is correct
62 Correct 4 ms 7628 KB Output is correct
63 Correct 4 ms 7628 KB Output is correct
64 Correct 4 ms 7604 KB Output is correct
65 Correct 262 ms 26440 KB Output is correct
66 Correct 254 ms 22832 KB Output is correct
67 Correct 258 ms 26816 KB Output is correct
68 Correct 253 ms 20932 KB Output is correct
69 Correct 6 ms 7628 KB Output is correct
70 Correct 4 ms 7628 KB Output is correct
71 Correct 4 ms 7636 KB Output is correct
72 Correct 4 ms 7628 KB Output is correct
73 Correct 3 ms 7372 KB Output is correct
74 Correct 4 ms 7384 KB Output is correct
75 Correct 4 ms 7628 KB Output is correct
76 Correct 4 ms 7636 KB Output is correct
77 Correct 4 ms 7628 KB Output is correct
78 Correct 4 ms 7628 KB Output is correct
79 Correct 4 ms 7628 KB Output is correct
80 Correct 4 ms 7628 KB Output is correct
81 Correct 5 ms 7636 KB Output is correct
82 Correct 4 ms 7628 KB Output is correct
83 Correct 4 ms 7628 KB Output is correct