#include<bits/stdc++.h>
using namespace std;
#define int long long
const int N = 1e5 + 5;
vector<pair<pair<int , int> , int> > edge;
vector<pair<int , int> > g[N];
int dp[N][2] , level[N] , d , e , n , q , w , last , star = -1;
bool ch = 1;
multiset<int , greater<int>> st;
void dfs(int ver , int par){
for(auto i : g[ver]){
int uu = i.first , ww = i.second;
if(uu == par) continue;
level[uu] = level[ver] + ww;
dfs(uu , ver);
}
}
void cal(){
for(int i = 1 ; i <= n ; i++) g[i].clear();
for(auto i : edge){
int U = i.first.first , V = i.first.second , W = i.second;
g[U].push_back({V , W});
g[V].push_back({U , W});
}
dfs(1 , 0);
int mx = 0 , vr = 1;
for(int i = 1 ; i <= n ; i++){
if(mx < level[i]){
mx = level[i];
vr = i;
}
}
level[vr] = 0;
dfs(vr , 0);
mx = 0;
for(int i = 1 ; i <= n ; i++)
mx = max(mx , level[i]);
cout << mx << '\n';
last = mx;
return;
}
void solve1(){
while(q--){
cin >> d >> e;
d = (d + last) % (n - 1);
e = (e + last) % w;
pair<pair<int , int> , int> p;
p = edge[d];
p.second = e;
swap(edge[d] , p);
cal();
}
}
void solve2(){
for(auto i : edge)
st.insert(i.second);
while(q--){
cin >> d >> e;
d = (d + last) % (n - 1);
e = (e + last) % w;
st.erase(st.find(edge[d].second));
pair<pair<int , int> , int> p;
p = edge[d];
p.second = e;
swap(edge[d] , p);
st.insert(e);
last = *st.begin() + *next(st.begin());
cout << last << '\n';
}
}
void pre(int ver , int pr){
st.erase(st.find(dp[ver][0]));
int mxx = 0;
for(int i = 0 ; i < (int)g[ver].size() ; i++){
int uu = g[ver][i].first , ww = g[ver][i].second;
if(uu == pr) continue;
dp[ver][0] = max(dp[ver][0] , dp[uu][1] + ww + mxx);
mxx = max(mxx , dp[uu][1] + ww);
dp[ver][1] = max(dp[ver][1] , dp[uu][1] + ww);
}
st.insert(dp[ver][0]);
}
void dfs2(int ver , int par){
if(g[ver].size() == 1) return;
for(auto i : g[ver]){
int uu = i.first , ww = i.second;
if(uu == par) continue;
dfs2(uu , ver);
}
pre(ver , par);
}
void solve3(){
dfs2(1 , 0);
while(q--){
cin >> d >> e;
d = (d + last) % (n - 1);
e = (e + last) % w;
int uu = edge[d].first.first , vv = edge[d].first.second;
pair<pair<int , int> , int> p;
p = edge[d];
p.second = e;
swap(edge[d] , p);
if(uu > vv) swap(uu , vv);
pre(uu , uu / 2);
while(uu != 1){
uu /= 2;
pre(uu , uu / 2);
}
last = *st.begin();
cout << last << '\n';
}
}
int32_t main(){
ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
cin >> n >> q >> w;
for(int i = 0 ; i < n - 1 ; i++){
int U , V , W;
cin >> U >> V >> W;
g[U].push_back({V , W});
g[V].push_back({U , W});
edge.push_back({{U , V} , W});
if(g[U].size() == n - 1) star = U;
if(g[V].size() == n - 1) star = V;
if(U > V) swap(U , V);
if(abs(V - 2 * U) > 1) ch = 0;
}
if(n <= 5000 && q <= 5000){
solve1();
return 0;
}
if(star != -1){
solve2();
return 0;
}
if(ch){
solve3();
return 0;
}
return 0;
}
Compilation message
diameter.cpp: In function 'void dfs2(long long int, long long int)':
diameter.cpp:101:22: warning: unused variable 'ww' [-Wunused-variable]
101 | int uu = i.first , ww = i.second;
| ^~
diameter.cpp: In function 'int32_t main()':
diameter.cpp:139:18: warning: comparison of integer expressions of different signedness: 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} and 'long long int' [-Wsign-compare]
139 | if(g[U].size() == n - 1) star = U;
| ~~~~~~~~~~~~^~~~~~~~
diameter.cpp:140:18: warning: comparison of integer expressions of different signedness: 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} and 'long long int' [-Wsign-compare]
140 | if(g[V].size() == n - 1) star = V;
| ~~~~~~~~~~~~^~~~~~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
2644 KB |
Output is correct |
2 |
Correct |
2 ms |
2644 KB |
Output is correct |
3 |
Correct |
1 ms |
2644 KB |
Output is correct |
4 |
Correct |
1 ms |
2644 KB |
Output is correct |
5 |
Correct |
2 ms |
2644 KB |
Output is correct |
6 |
Correct |
3 ms |
2644 KB |
Output is correct |
7 |
Correct |
2 ms |
2644 KB |
Output is correct |
8 |
Correct |
2 ms |
2644 KB |
Output is correct |
9 |
Correct |
2 ms |
2644 KB |
Output is correct |
10 |
Correct |
2 ms |
2644 KB |
Output is correct |
11 |
Correct |
2 ms |
2644 KB |
Output is correct |
12 |
Correct |
2 ms |
2644 KB |
Output is correct |
13 |
Correct |
2 ms |
2644 KB |
Output is correct |
14 |
Correct |
2 ms |
2644 KB |
Output is correct |
15 |
Correct |
2 ms |
2644 KB |
Output is correct |
16 |
Correct |
2 ms |
2580 KB |
Output is correct |
17 |
Correct |
2 ms |
2644 KB |
Output is correct |
18 |
Correct |
3 ms |
2644 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
2644 KB |
Output is correct |
2 |
Correct |
2 ms |
2644 KB |
Output is correct |
3 |
Correct |
1 ms |
2644 KB |
Output is correct |
4 |
Correct |
1 ms |
2644 KB |
Output is correct |
5 |
Correct |
2 ms |
2644 KB |
Output is correct |
6 |
Correct |
3 ms |
2644 KB |
Output is correct |
7 |
Correct |
2 ms |
2644 KB |
Output is correct |
8 |
Correct |
2 ms |
2644 KB |
Output is correct |
9 |
Correct |
2 ms |
2644 KB |
Output is correct |
10 |
Correct |
2 ms |
2644 KB |
Output is correct |
11 |
Correct |
2 ms |
2644 KB |
Output is correct |
12 |
Correct |
2 ms |
2644 KB |
Output is correct |
13 |
Correct |
2 ms |
2644 KB |
Output is correct |
14 |
Correct |
2 ms |
2644 KB |
Output is correct |
15 |
Correct |
2 ms |
2644 KB |
Output is correct |
16 |
Correct |
2 ms |
2580 KB |
Output is correct |
17 |
Correct |
2 ms |
2644 KB |
Output is correct |
18 |
Correct |
3 ms |
2644 KB |
Output is correct |
19 |
Correct |
244 ms |
2756 KB |
Output is correct |
20 |
Correct |
241 ms |
2764 KB |
Output is correct |
21 |
Correct |
237 ms |
2772 KB |
Output is correct |
22 |
Correct |
256 ms |
2792 KB |
Output is correct |
23 |
Correct |
1589 ms |
3164 KB |
Output is correct |
24 |
Correct |
1665 ms |
3272 KB |
Output is correct |
25 |
Correct |
1684 ms |
3176 KB |
Output is correct |
26 |
Correct |
1673 ms |
3332 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
2644 KB |
Output is correct |
2 |
Correct |
2 ms |
2644 KB |
Output is correct |
3 |
Correct |
4 ms |
2644 KB |
Output is correct |
4 |
Correct |
9 ms |
2772 KB |
Output is correct |
5 |
Correct |
32 ms |
3028 KB |
Output is correct |
6 |
Correct |
3 ms |
2644 KB |
Output is correct |
7 |
Correct |
3 ms |
2644 KB |
Output is correct |
8 |
Correct |
6 ms |
2644 KB |
Output is correct |
9 |
Correct |
38 ms |
2644 KB |
Output is correct |
10 |
Correct |
11 ms |
2760 KB |
Output is correct |
11 |
Correct |
36 ms |
3164 KB |
Output is correct |
12 |
Correct |
4 ms |
3164 KB |
Output is correct |
13 |
Correct |
4 ms |
3156 KB |
Output is correct |
14 |
Correct |
5 ms |
3284 KB |
Output is correct |
15 |
Correct |
12 ms |
3284 KB |
Output is correct |
16 |
Correct |
45 ms |
3796 KB |
Output is correct |
17 |
Correct |
69 ms |
14396 KB |
Output is correct |
18 |
Correct |
59 ms |
14352 KB |
Output is correct |
19 |
Correct |
58 ms |
14316 KB |
Output is correct |
20 |
Correct |
72 ms |
14492 KB |
Output is correct |
21 |
Correct |
161 ms |
15008 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
41 ms |
2764 KB |
Output is correct |
2 |
Execution timed out |
5052 ms |
2644 KB |
Time limit exceeded |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
76 ms |
10236 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
2644 KB |
Output is correct |
2 |
Correct |
2 ms |
2644 KB |
Output is correct |
3 |
Correct |
1 ms |
2644 KB |
Output is correct |
4 |
Correct |
1 ms |
2644 KB |
Output is correct |
5 |
Correct |
2 ms |
2644 KB |
Output is correct |
6 |
Correct |
3 ms |
2644 KB |
Output is correct |
7 |
Correct |
2 ms |
2644 KB |
Output is correct |
8 |
Correct |
2 ms |
2644 KB |
Output is correct |
9 |
Correct |
2 ms |
2644 KB |
Output is correct |
10 |
Correct |
2 ms |
2644 KB |
Output is correct |
11 |
Correct |
2 ms |
2644 KB |
Output is correct |
12 |
Correct |
2 ms |
2644 KB |
Output is correct |
13 |
Correct |
2 ms |
2644 KB |
Output is correct |
14 |
Correct |
2 ms |
2644 KB |
Output is correct |
15 |
Correct |
2 ms |
2644 KB |
Output is correct |
16 |
Correct |
2 ms |
2580 KB |
Output is correct |
17 |
Correct |
2 ms |
2644 KB |
Output is correct |
18 |
Correct |
3 ms |
2644 KB |
Output is correct |
19 |
Correct |
244 ms |
2756 KB |
Output is correct |
20 |
Correct |
241 ms |
2764 KB |
Output is correct |
21 |
Correct |
237 ms |
2772 KB |
Output is correct |
22 |
Correct |
256 ms |
2792 KB |
Output is correct |
23 |
Correct |
1589 ms |
3164 KB |
Output is correct |
24 |
Correct |
1665 ms |
3272 KB |
Output is correct |
25 |
Correct |
1684 ms |
3176 KB |
Output is correct |
26 |
Correct |
1673 ms |
3332 KB |
Output is correct |
27 |
Correct |
1 ms |
2644 KB |
Output is correct |
28 |
Correct |
2 ms |
2644 KB |
Output is correct |
29 |
Correct |
4 ms |
2644 KB |
Output is correct |
30 |
Correct |
9 ms |
2772 KB |
Output is correct |
31 |
Correct |
32 ms |
3028 KB |
Output is correct |
32 |
Correct |
3 ms |
2644 KB |
Output is correct |
33 |
Correct |
3 ms |
2644 KB |
Output is correct |
34 |
Correct |
6 ms |
2644 KB |
Output is correct |
35 |
Correct |
38 ms |
2644 KB |
Output is correct |
36 |
Correct |
11 ms |
2760 KB |
Output is correct |
37 |
Correct |
36 ms |
3164 KB |
Output is correct |
38 |
Correct |
4 ms |
3164 KB |
Output is correct |
39 |
Correct |
4 ms |
3156 KB |
Output is correct |
40 |
Correct |
5 ms |
3284 KB |
Output is correct |
41 |
Correct |
12 ms |
3284 KB |
Output is correct |
42 |
Correct |
45 ms |
3796 KB |
Output is correct |
43 |
Correct |
69 ms |
14396 KB |
Output is correct |
44 |
Correct |
59 ms |
14352 KB |
Output is correct |
45 |
Correct |
58 ms |
14316 KB |
Output is correct |
46 |
Correct |
72 ms |
14492 KB |
Output is correct |
47 |
Correct |
161 ms |
15008 KB |
Output is correct |
48 |
Correct |
41 ms |
2764 KB |
Output is correct |
49 |
Execution timed out |
5052 ms |
2644 KB |
Time limit exceeded |
50 |
Halted |
0 ms |
0 KB |
- |