#include <bits/stdc++.h>
#define eb emplace_back
#define mp make_pair
#define F first
#define S second
#define printv(a, b) { \
for(auto pv : a) b << pv << " "; \
b << "\n"; \
}
using namespace std;
using pii = pair<int, int>;
const int MAX = 1e9;
map<string, int> id;
int num = 1;
int getid(string& s){
if(id.find(s) == id.end()) id[s] = num++;
return id[s];
}
int n;
vector<vector<int>> g;
vector<int> dp0, dp1;
vector<bool> vst, vst2;
vector<int> f;
void init(){
g.resize(n + 1);
dp0.resize(n + 1);
dp1.resize(n + 1);
vst.resize(n + 1);
vst2.resize(n + 1);
f.resize(n + 1);
}
void dfs(int now){
vst[now] = true;
int sum = 0, mn = n;
int cnt = 0;
for(int i : g[now]){
if(vst2[i]) continue;
dfs(i);
cnt++;
sum += dp1[i];
mn = min(mn, dp0[i] - dp1[i]);
}
if(cnt == 0){
dp0[now] = 0; dp1[now] = 1;
}
else{
dp0[now] = sum;
dp1[now] = sum + mn + 1;
}
}
int solve(int s){
//cerr << "solve\n";
while(!vst[s]){
vst[s] = true;
s = f[s];
}
vector<int> cy;
int v = s;
do{
vst2[v] = vst[v] = true;
cy.eb(v);
v = f[v];
}
while(v != s);
//printv(cy, cerr);
for(int i : cy) dfs(i);
vector<vector<int>> dps(3, vector<int>(3, MAX));
dps[0][0] = dp0[cy[0]];
dps[1][1] = dp0[cy[0]] + 1;
dps[2][2] = dp1[cy[0]];
for(int i = 1; i < cy.size(); i++){
int now = cy[i];
vector<vector<int>> dps2(3, vector<int>(3, MAX));
for(int fst = 0; fst < 3; fst++){
dps2[fst][0] = min(dps[fst][1], dps[fst][2]) + dp0[now];
dps2[fst][1] = min({dps[fst][0], dps[fst][1], dps[fst][2]}) + dp0[now] + 1;
dps2[fst][2] = min(dps[fst][1], dps[fst][2]) + dp1[now];
}
dps = dps2;
}
int ans = MAX;
ans = min({ans, dps[0][1], dps[0][2]});
ans = min({ans, dps[1][0], dps[1][1], dps[1][2]});
ans = min({ans, dps[2][1], dps[2][2]});
if(cy.size() == 2) ans = min(ans, dp0[cy[0]] + dp0[cy[1]]);
//cerr << "solve ok " << ans << "\n";
return ans;
}
int main(){
ios_base::sync_with_stdio(false);
cin.tie(0);
cin >> n;
init();
for(int i = 1; i <= n; i++){
string s, t;
cin >> s >> t;
int u = getid(s), v = getid(t);
f[u] = v;
}
for(int i = 1; i <= n; i++){
g[f[i]].eb(i);
}
//for(auto& i : id) cerr << i.F << " " << i.S << "\n";
if(n % 2){
cout << "-1\n";
return 0;
}
int ans = 0;
for(int i = 1; i <= n; i++){
if(vst[i]) continue;
ans += solve(i);
}
//printv(dp0, cerr);
//printv(dp1, cerr);
cout << ans << "\n";
return 0;
}
Compilation message
polygon.cpp: In function 'int solve(int)':
polygon.cpp:85:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
85 | for(int i = 1; i < cy.size(); i++){
| ~~^~~~~~~~~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
204 KB |
Output is correct |
2 |
Correct |
0 ms |
204 KB |
Output is correct |
3 |
Correct |
0 ms |
204 KB |
Output is correct |
4 |
Correct |
0 ms |
204 KB |
Output is correct |
5 |
Correct |
0 ms |
204 KB |
Output is correct |
6 |
Correct |
0 ms |
204 KB |
Output is correct |
7 |
Correct |
0 ms |
204 KB |
Output is correct |
8 |
Correct |
1 ms |
204 KB |
Output is correct |
9 |
Correct |
0 ms |
204 KB |
Output is correct |
10 |
Correct |
0 ms |
204 KB |
Output is correct |
11 |
Correct |
0 ms |
204 KB |
Output is correct |
12 |
Correct |
0 ms |
204 KB |
Output is correct |
13 |
Correct |
0 ms |
204 KB |
Output is correct |
14 |
Correct |
0 ms |
204 KB |
Output is correct |
15 |
Correct |
0 ms |
204 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
204 KB |
Output is correct |
2 |
Correct |
1 ms |
204 KB |
Output is correct |
3 |
Correct |
0 ms |
204 KB |
Output is correct |
4 |
Correct |
196 ms |
15340 KB |
Output is correct |
5 |
Correct |
208 ms |
16836 KB |
Output is correct |
6 |
Correct |
201 ms |
17576 KB |
Output is correct |
7 |
Correct |
173 ms |
16956 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
178 ms |
13964 KB |
Output is correct |
2 |
Correct |
212 ms |
16128 KB |
Output is correct |
3 |
Correct |
185 ms |
14756 KB |
Output is correct |
4 |
Correct |
184 ms |
13188 KB |
Output is correct |
5 |
Correct |
192 ms |
21976 KB |
Output is correct |
6 |
Correct |
185 ms |
13200 KB |
Output is correct |
7 |
Correct |
172 ms |
13292 KB |
Output is correct |
8 |
Correct |
200 ms |
13636 KB |
Output is correct |
9 |
Correct |
157 ms |
12792 KB |
Output is correct |
10 |
Correct |
136 ms |
12260 KB |
Output is correct |
11 |
Correct |
0 ms |
204 KB |
Output is correct |
12 |
Correct |
0 ms |
204 KB |
Output is correct |
13 |
Correct |
0 ms |
204 KB |
Output is correct |
14 |
Correct |
0 ms |
204 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
204 KB |
Output is correct |
2 |
Correct |
0 ms |
204 KB |
Output is correct |
3 |
Correct |
0 ms |
204 KB |
Output is correct |
4 |
Correct |
0 ms |
204 KB |
Output is correct |
5 |
Correct |
0 ms |
204 KB |
Output is correct |
6 |
Correct |
0 ms |
204 KB |
Output is correct |
7 |
Correct |
0 ms |
204 KB |
Output is correct |
8 |
Correct |
1 ms |
204 KB |
Output is correct |
9 |
Correct |
0 ms |
204 KB |
Output is correct |
10 |
Correct |
0 ms |
204 KB |
Output is correct |
11 |
Correct |
0 ms |
204 KB |
Output is correct |
12 |
Correct |
0 ms |
204 KB |
Output is correct |
13 |
Correct |
0 ms |
204 KB |
Output is correct |
14 |
Correct |
0 ms |
204 KB |
Output is correct |
15 |
Correct |
0 ms |
204 KB |
Output is correct |
16 |
Correct |
0 ms |
204 KB |
Output is correct |
17 |
Correct |
1 ms |
204 KB |
Output is correct |
18 |
Correct |
0 ms |
204 KB |
Output is correct |
19 |
Correct |
196 ms |
15340 KB |
Output is correct |
20 |
Correct |
208 ms |
16836 KB |
Output is correct |
21 |
Correct |
201 ms |
17576 KB |
Output is correct |
22 |
Correct |
173 ms |
16956 KB |
Output is correct |
23 |
Correct |
178 ms |
13964 KB |
Output is correct |
24 |
Correct |
212 ms |
16128 KB |
Output is correct |
25 |
Correct |
185 ms |
14756 KB |
Output is correct |
26 |
Correct |
184 ms |
13188 KB |
Output is correct |
27 |
Correct |
192 ms |
21976 KB |
Output is correct |
28 |
Correct |
185 ms |
13200 KB |
Output is correct |
29 |
Correct |
172 ms |
13292 KB |
Output is correct |
30 |
Correct |
200 ms |
13636 KB |
Output is correct |
31 |
Correct |
157 ms |
12792 KB |
Output is correct |
32 |
Correct |
136 ms |
12260 KB |
Output is correct |
33 |
Correct |
0 ms |
204 KB |
Output is correct |
34 |
Correct |
0 ms |
204 KB |
Output is correct |
35 |
Correct |
0 ms |
204 KB |
Output is correct |
36 |
Correct |
0 ms |
204 KB |
Output is correct |
37 |
Correct |
185 ms |
16568 KB |
Output is correct |
38 |
Correct |
208 ms |
15836 KB |
Output is correct |
39 |
Correct |
178 ms |
15492 KB |
Output is correct |
40 |
Correct |
208 ms |
15404 KB |
Output is correct |
41 |
Correct |
179 ms |
15396 KB |
Output is correct |
42 |
Correct |
188 ms |
15820 KB |
Output is correct |
43 |
Correct |
175 ms |
15812 KB |
Output is correct |
44 |
Correct |
192 ms |
15876 KB |
Output is correct |
45 |
Correct |
180 ms |
15796 KB |
Output is correct |
46 |
Correct |
185 ms |
15828 KB |
Output is correct |
47 |
Correct |
183 ms |
15004 KB |
Output is correct |
48 |
Correct |
176 ms |
16136 KB |
Output is correct |
49 |
Correct |
200 ms |
18156 KB |
Output is correct |
50 |
Correct |
161 ms |
16912 KB |
Output is correct |
51 |
Correct |
163 ms |
15400 KB |
Output is correct |
52 |
Correct |
206 ms |
24152 KB |
Output is correct |
53 |
Correct |
181 ms |
15452 KB |
Output is correct |
54 |
Correct |
179 ms |
15328 KB |
Output is correct |
55 |
Correct |
167 ms |
15756 KB |
Output is correct |
56 |
Correct |
170 ms |
14920 KB |
Output is correct |
57 |
Correct |
152 ms |
14464 KB |
Output is correct |
58 |
Correct |
0 ms |
312 KB |
Output is correct |
59 |
Correct |
1 ms |
204 KB |
Output is correct |
60 |
Correct |
0 ms |
316 KB |
Output is correct |
61 |
Correct |
0 ms |
204 KB |
Output is correct |
62 |
Correct |
0 ms |
204 KB |
Output is correct |
63 |
Correct |
0 ms |
204 KB |
Output is correct |
64 |
Correct |
0 ms |
300 KB |
Output is correct |
65 |
Correct |
201 ms |
17628 KB |
Output is correct |
66 |
Correct |
225 ms |
16876 KB |
Output is correct |
67 |
Correct |
190 ms |
17572 KB |
Output is correct |
68 |
Correct |
216 ms |
16908 KB |
Output is correct |
69 |
Correct |
0 ms |
204 KB |
Output is correct |
70 |
Correct |
1 ms |
204 KB |
Output is correct |
71 |
Correct |
0 ms |
204 KB |
Output is correct |
72 |
Correct |
0 ms |
204 KB |
Output is correct |
73 |
Correct |
1 ms |
312 KB |
Output is correct |
74 |
Correct |
0 ms |
204 KB |
Output is correct |
75 |
Correct |
1 ms |
312 KB |
Output is correct |
76 |
Correct |
1 ms |
204 KB |
Output is correct |
77 |
Correct |
1 ms |
204 KB |
Output is correct |
78 |
Correct |
0 ms |
204 KB |
Output is correct |
79 |
Correct |
0 ms |
204 KB |
Output is correct |
80 |
Correct |
0 ms |
308 KB |
Output is correct |
81 |
Correct |
0 ms |
300 KB |
Output is correct |
82 |
Correct |
1 ms |
312 KB |
Output is correct |
83 |
Correct |
1 ms |
204 KB |
Output is correct |