#include <iostream>
#include <vector>
#include <unordered_map>
#include <queue>
const int N = 100000;
const long long inf = 9e18;
using namespace std;
long long z[N];
struct edge {
int neigh;
long long charge;
};
struct change_charge {
int a;
int b;
long long charge;
};
struct change_gain {
int city;
long long gain;
};
struct toBfs {
int nrCity;
long long loss;
};
vector<edge> country[N+5];
bool visited[N+5];
vector<int> result;
unordered_map<int, change_charge> charges;
unordered_map<int, change_gain> profits;
int main()
{
std::ios_base::sync_with_stdio(false);
int n, q, a, b, v, type;
long long c, d;
cin >> n >> q;
for(int i=1; i<=n; i++)
cin >> z[i];
for(int i=1; i<n; i++)
{
cin >> a >> b >> c;
country[a].push_back({b, c});
country[b].push_back({a, c});
}
for(int i=1; i<=q; i++)
{
cin >> type;
if(type==1)
{
cin >> v >> d;
profits[i] = {v, d};
}
else
{
cin >> a >> b >> d;
charges[i] = {a, b, d};
}
}
int s = 1;
for(int i=1; i<=q; i++)
{
auto it = profits.find(i);
if(it==profits.end())
{
auto it2 = charges.find(i);
for(auto& child : country[(it2->second).a]) {
if(child.neigh==(it2->second).b)
child.charge = (it2->second).charge;
}
for(auto& child : country[(it2->second).b]) {
if(child.neigh==(it2->second).a)
child.charge = (it2->second).charge;
}
}
else
{
z[(it->second).city] = (it->second).gain;
}
int maxCity = 0, traverseCities = 0;
long long maxResult = -inf;
for(int j=1; j<=n; j++) visited[j] = false;
queue<toBfs> q;
visited[s] = true;
q.push({s, 0});
while(!q.empty())
{
auto source = q.front();
q.pop();
for(auto& child : country[source.nrCity])
{
if(!visited[child.neigh])
{
long long newLoss = source.loss - child.charge;
visited[child.neigh] = true;
long long eh = (z[child.neigh] + newLoss);
if(eh > maxResult)
{
maxResult = eh;
maxCity = child.neigh;
} else if(eh == maxResult) {
if(maxCity > child.neigh)
maxCity = child.neigh;
}
q.push({child.neigh, newLoss});
traverseCities++;
}
}
}
result.push_back(maxCity);
s = maxCity;
}
for(int i=0; i<q; i++)
{
cout << result[i] << " ";
}
cout << endl;
return 0;
}
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 | #include <iostream> #include <vector> #include <unordered_map> #include <queue> const int N = 100000; const long long inf = 9e18; using namespace std; long long z[N]; struct edge { int neigh; long long charge; }; struct change_charge { int a; int b; long long charge; }; struct change_gain { int city; long long gain; }; struct toBfs { int nrCity; long long loss; }; vector<edge> country[N+5]; bool visited[N+5]; vector<int> result; unordered_map<int, change_charge> charges; unordered_map<int, change_gain> profits; int main() { std::ios_base::sync_with_stdio(false); int n, q, a, b, v, type; long long c, d; cin >> n >> q; for(int i=1; i<=n; i++) cin >> z[i]; for(int i=1; i<n; i++) { cin >> a >> b >> c; country[a].push_back({b, c}); country[b].push_back({a, c}); } for(int i=1; i<=q; i++) { cin >> type; if(type==1) { cin >> v >> d; profits[i] = {v, d}; } else { cin >> a >> b >> d; charges[i] = {a, b, d}; } } int s = 1; for(int i=1; i<=q; i++) { auto it = profits.find(i); if(it==profits.end()) { auto it2 = charges.find(i); for(auto& child : country[(it2->second).a]) { if(child.neigh==(it2->second).b) child.charge = (it2->second).charge; } for(auto& child : country[(it2->second).b]) { if(child.neigh==(it2->second).a) child.charge = (it2->second).charge; } } else { z[(it->second).city] = (it->second).gain; } int maxCity = 0, traverseCities = 0; long long maxResult = -inf; for(int j=1; j<=n; j++) visited[j] = false; queue<toBfs> q; visited[s] = true; q.push({s, 0}); while(!q.empty()) { auto source = q.front(); q.pop(); for(auto& child : country[source.nrCity]) { if(!visited[child.neigh]) { long long newLoss = source.loss - child.charge; visited[child.neigh] = true; long long eh = (z[child.neigh] + newLoss); if(eh > maxResult) { maxResult = eh; maxCity = child.neigh; } else if(eh == maxResult) { if(maxCity > child.neigh) maxCity = child.neigh; } q.push({child.neigh, newLoss}); traverseCities++; } } } result.push_back(maxCity); s = maxCity; } for(int i=0; i<q; i++) { cout << result[i] << " "; } cout << endl; return 0; } |
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