#include "bits/stdc++.h"
#define all(v) begin(v), end(v)
#define dbg(x) "[" #x " = " << (x) << "]"
using namespace std;
struct edge{
int v, flow, cap;
edge(int v, int flow, int cap) : v(v), flow(flow), cap(cap) {}
};
struct Dinic{
vector<int> level, ptr;
vector<vector<int>> adj;
vector<edge> edges;
queue<int> q;
Dinic(int n) :
level(n),
ptr(n),
adj(n),
edges(),
q()
{}
void addEdge(int u, int v, int c){
adj[u].push_back((int)edges.size());
edges.push_back(edge(v, 0, c));
adj[v].push_back((int)edges.size());
edges.push_back(edge(u, 0, c));
}
bool bfs(int s, int t){
fill(all(level), -1);
level[s] = 0;
q.push(s);
while(!q.empty()){
int u = q.front(); q.pop();
for(int id : adj[u]){
int v = edges[id].v;
if(level[v] == -1 && edges[id].flow < edges[id].cap){
level[v] = level[u] + 1;
q.push(v);
}
}
}
return level[t] != -1;
}
int dfs(int u, int inc, int t){
if(u == t) return inc;
for(; ptr[u] < (int)adj[u].size(); ++ptr[u]){
int id = adj[u][ptr[u]];
int v = edges[id].v;
if(level[u] + 1 == level[v] && edges[id].flow < edges[id].cap){
int delta = dfs(v, min(inc, edges[id].cap - edges[id].flow), t);
if(delta > 0){
edges[id].flow += delta;
edges[id ^ 1].flow -= delta;
return delta;
}
}
}
return 0;
}
int maxflow(int s, int t){
int sumflow = 0;
while(bfs(s, t)){
fill(all(ptr), 0);
while(int pushed = dfs(s, 1e9, t) > 0){
sumflow += pushed;
}
}
return sumflow;
}
};
const int MAX = 7e4 + 5;
const int inf = 1e9 + 7;
int n, depth[MAX], queries[MAX], par[MAX], head[MAX], minEdge[MAX], maxEdge[MAX];
int id_minEdge_in_network[MAX], id_maxEdge_in_network[MAX], timerHLD;
vector<int> adj[MAX];
/*
Note :
minEdge[i] -> id of minimum edge (i, par[i])
maxEdge[i] -> id of maximum edge (i, par[i])
*/
int lab[MAX];
int find_root(int u){
return lab[u] == u ? u : (lab[u] = find_root(lab[u]));
}
bool unite(int u, int v){
u = find_root(u);
v = find_root(v);
if(u == v) return false;
// if(lab[u] > lab[v]) swap(u, v);
lab[u] += lab[v];
lab[v] = u;
return true;
}
void assign_min_path(int u, int v, int id){
while(true){
u = find_root(u);
v = find_root(v);
if(u == v) return;
if(depth[u] < depth[v]) swap(u, v);
minEdge[u] = id;
lab[u] = par[u];
}
}
void assign_max_path(int u, int v, int id){
while(true){
u = find_root(u);
v = find_root(v);
if(u == v) return;
if(depth[u] < depth[v]) swap(u, v);
maxEdge[u] = id;
lab[u] = par[u];
}
}
void dfs(int u){
for(int& v : adj[u]){
adj[v].erase(find(all(adj[v]), u));
depth[v] = depth[u] + 1;
par[v] = u;
dfs(v);
}
}
void initDSU(){
for(int i = 0; i < n; ++i) lab[i] = i;
}
int main(){
ios_base::sync_with_stdio(0);
cin.tie(0);
if(fopen("task.inp", "r")){
freopen("task.inp", "r", stdin);
freopen("task.out", "w", stdout);
}
cin >> n;
for(int i = 1; i < n; ++i){
int u, v;
cin >> u >> v;
--u, --v;
adj[u].push_back(v);
adj[v].push_back(u);
}
dfs(0);
int k; cin >> k;
vector<tuple<int, int, int, int>> minPaints, maxPaints;
for(int i = 0; i < k; ++i){
char op; int u, v, w;
cin >> op >> u >> v >> w;
--u, --v;
if(op == 'm') minPaints.push_back({w, u, v, i});
else maxPaints.push_back({w, u, v, i});
queries[i] = w;
}
sort(all(minPaints), greater<tuple<int, int, int, int>>());
sort(all(maxPaints));
memset(minEdge, -1, sizeof(minEdge));
memset(maxEdge, -1, sizeof(maxEdge));
initDSU();
for(auto [w, u, v, i] : minPaints){
assign_min_path(u, v, i);
}
initDSU();
for(auto [w, u, v, i] : maxPaints){
assign_max_path(u, v, i);
}
int s = 0, t = n + k + 1;
Dinic Network(n + k + 2);
for(int i = 1; i < n; ++i){
Network.addEdge(s, i, 1);
}
for(int i = 0; i < k; ++i){
Network.addEdge(n + i + 1, t, 1);
}
for(int i = 1; i < n; ++i){
if(minEdge[i] != -1){
id_minEdge_in_network[i] = (int)Network.edges.size();
Network.addEdge(i, n + minEdge[i] + 1, 1);
}
if(maxEdge[i] != -1){
id_maxEdge_in_network[i] = (int)Network.edges.size();
Network.addEdge(i, n + maxEdge[i] + 1, 1);
}
// cout << minEdge[i] << ' ' << maxEdge[i] << ' ' << dbg(i + 1) << '\n';
}
int ret = Network.maxflow(s, t);
for(int i = 1; i < n; ++i){
int res = -1;
cout << par[i] + 1 << ' ' << i + 1 << ' ';
if(minEdge[i] == -1 && maxEdge[i] == -1){
cout << inf << '\n';
} else{
if(minEdge[i] != -1 && (Network.edges[id_minEdge_in_network[i]].flow > 0 || maxEdge[i] == -1)) cout << queries[minEdge[i]] << "!\n";
else cout << queries[maxEdge[i]] << "?\n";
}
}
return 0;
}
Compilation message
minmaxtree.cpp: In function 'int main()':
minmaxtree.cpp:191:14: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
191 | for(auto [w, u, v, i] : minPaints){
| ^
minmaxtree.cpp:196:14: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
196 | for(auto [w, u, v, i] : maxPaints){
| ^
minmaxtree.cpp:228:13: warning: unused variable 'res' [-Wunused-variable]
228 | int res = -1;
| ^~~
minmaxtree.cpp:225:9: warning: unused variable 'ret' [-Wunused-variable]
225 | int ret = Network.maxflow(s, t);
| ^~~
minmaxtree.cpp:155:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
155 | freopen("task.inp", "r", stdin);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
minmaxtree.cpp:156:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
156 | freopen("task.out", "w", stdout);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
2 ms |
2652 KB |
Expected integer, but "19!" found |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
80 ms |
28628 KB |
Expected integer, but "571006141?" found |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
61 ms |
20176 KB |
Expected integer, but "104540451?" found |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
2 ms |
2652 KB |
Expected integer, but "19!" found |
| 2 |
Halted |
0 ms |
0 KB |
- |
