#include <iostream>
#include <vector>
#include <queue>
#include <climits>
using namespace std;
const int N = 100004;
long long z[N];
bool visited[N];
long long totalCost[N];
vector<int> tree[N];
vector<long long> cost[N];
int main() {
ios_base::sync_with_stdio(0);
int n, q;
cin >> n >> q;
for (int i = 1; i <= n; i++) {
cin >> z[i];
}
int a, b;
long long c;
for (int i = 0; i < n - 1; i++) {
cin >> a >> b >> c;
tree[a].push_back(b);
tree[b].push_back(a);
cost[b].push_back(c);
cost[a].push_back(c);
}
int type;
long long v, d;
int city = 1;
while (q --> 0) {
cin >> type;
if (type == 1) {
cin >> v >> d;
z[v] = d;
} else {
cin >> a >> b >> d;
for (int i = 0; i < tree[a].size(); i++) {
if (tree[a][i] == b) {
cost[a][i] = d;
break;
}
}
for (int i = 0; i < tree[b].size(); i++) {
if (tree[b][i] == a) {
cost[b][i] = d;
break;
}
}
}
for (int i = 0; i <= n; i++) {
visited[i] = 0;
}
queue<int> Q;
Q.push(city);
long long maxx = LLONG_MIN;
int newCity = -1;
totalCost[city] = 0;
while (!Q.empty()) {
int tmp = Q.front();
Q.pop();
visited[tmp] = 1;
for (int i = 0; i < tree[tmp].size(); i++) {
if (visited[tree[tmp][i]] == 0) {
Q.push(tree[tmp][i]);
totalCost[tree[tmp][i]] = totalCost[tmp] + cost[tmp][i];
}
}
}
bool isFirst = true;
for (int i = 1; i <= n; i++) {
if (i != city) {
if (isFirst || z[i] - totalCost[i] > maxx) {
maxx = z[i] - totalCost[i];
newCity = i;
isFirst = false;
}
}
}
cout << newCity << " ";
city = newCity;
}
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 | #include <iostream> #include <vector> #include <queue> #include <climits> using namespace std; const int N = 100004; long long z[N]; bool visited[N]; long long totalCost[N]; vector<int> tree[N]; vector<long long> cost[N]; int main() { ios_base::sync_with_stdio(0); int n, q; cin >> n >> q; for (int i = 1; i <= n; i++) { cin >> z[i]; } int a, b; long long c; for (int i = 0; i < n - 1; i++) { cin >> a >> b >> c; tree[a].push_back(b); tree[b].push_back(a); cost[b].push_back(c); cost[a].push_back(c); } int type; long long v, d; int city = 1; while (q --> 0) { cin >> type; if (type == 1) { cin >> v >> d; z[v] = d; } else { cin >> a >> b >> d; for (int i = 0; i < tree[a].size(); i++) { if (tree[a][i] == b) { cost[a][i] = d; break; } } for (int i = 0; i < tree[b].size(); i++) { if (tree[b][i] == a) { cost[b][i] = d; break; } } } for (int i = 0; i <= n; i++) { visited[i] = 0; } queue<int> Q; Q.push(city); long long maxx = LLONG_MIN; int newCity = -1; totalCost[city] = 0; while (!Q.empty()) { int tmp = Q.front(); Q.pop(); visited[tmp] = 1; for (int i = 0; i < tree[tmp].size(); i++) { if (visited[tree[tmp][i]] == 0) { Q.push(tree[tmp][i]); totalCost[tree[tmp][i]] = totalCost[tmp] + cost[tmp][i]; } } } bool isFirst = true; for (int i = 1; i <= n; i++) { if (i != city) { if (isFirst || z[i] - totalCost[i] > maxx) { maxx = z[i] - totalCost[i]; newCity = i; isFirst = false; } } } cout << newCity << " "; city = newCity; } return 0; } |
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