#include <algorithm> #include <vector> #include <map> #include <cstdio> #include <utility> const int MAX = 100001; using namespace std; class City { public: long long profit; map<int, int> neighbors; }; void findLargestProfit(City graph[MAX], int start, int root, long long cost, long long* max_profit, int* max_profit_city, bool visited[MAX]) { visited[start] = true; long long my_profit = graph[start].profit - cost; if (my_profit > *max_profit || *max_profit_city == root || (my_profit == *max_profit && start < *max_profit_city)) { *max_profit = my_profit; *max_profit_city = start; } for (map<int, int>::iterator iter = graph[start].neighbors.begin(); iter != graph[start].neighbors.end(); ++iter) { if (!visited[iter->first]) { findLargestProfit(graph, iter->first, root, cost + iter->second, max_profit, max_profit_city, visited); } } } int main() { int n, q; scanf("%d", &n); scanf("%d", &q); City graph[MAX]; bool visited[MAX]; long long profit; for (int i = 1; i < n + 1; ++i) { scanf("%lld", &profit); graph[i].profit = profit; } int from, to, toll; for (int i = 0; i < n - 1; ++i) { scanf("%d", &from); scanf("%d", &to); scanf("%d", &toll); graph[from].neighbors[to] = toll; graph[to].neighbors[from] = toll; } int opt, max_profit_city = 1; long long max_profit; for (int i = 0; i < q; ++i) { scanf("%d", &opt); if (opt == 1) { scanf("%d", &from); scanf("%lld", &graph[from].profit); } else { scanf("%d", &from); scanf("%d", &to); scanf("%d", &toll); graph[from].neighbors[to] = toll; graph[to].neighbors[from] = toll; } for (int j = 1; j < n + 1; ++j) visited[j] = false; max_profit = -1; findLargestProfit(graph, max_profit_city, max_profit_city, 0L, &max_profit, &max_profit_city, visited); printf("%d ", max_profit_city); } 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 | #include <algorithm> #include <vector> #include <map> #include <cstdio> #include <utility> const int MAX = 100001; using namespace std; class City { public: long long profit; map<int, int> neighbors; }; void findLargestProfit(City graph[MAX], int start, int root, long long cost, long long* max_profit, int* max_profit_city, bool visited[MAX]) { visited[start] = true; long long my_profit = graph[start].profit - cost; if (my_profit > *max_profit || *max_profit_city == root || (my_profit == *max_profit && start < *max_profit_city)) { *max_profit = my_profit; *max_profit_city = start; } for (map<int, int>::iterator iter = graph[start].neighbors.begin(); iter != graph[start].neighbors.end(); ++iter) { if (!visited[iter->first]) { findLargestProfit(graph, iter->first, root, cost + iter->second, max_profit, max_profit_city, visited); } } } int main() { int n, q; scanf("%d", &n); scanf("%d", &q); City graph[MAX]; bool visited[MAX]; long long profit; for (int i = 1; i < n + 1; ++i) { scanf("%lld", &profit); graph[i].profit = profit; } int from, to, toll; for (int i = 0; i < n - 1; ++i) { scanf("%d", &from); scanf("%d", &to); scanf("%d", &toll); graph[from].neighbors[to] = toll; graph[to].neighbors[from] = toll; } int opt, max_profit_city = 1; long long max_profit; for (int i = 0; i < q; ++i) { scanf("%d", &opt); if (opt == 1) { scanf("%d", &from); scanf("%lld", &graph[from].profit); } else { scanf("%d", &from); scanf("%d", &to); scanf("%d", &toll); graph[from].neighbors[to] = toll; graph[to].neighbors[from] = toll; } for (int j = 1; j < n + 1; ++j) visited[j] = false; max_profit = -1; findLargestProfit(graph, max_profit_city, max_profit_city, 0L, &max_profit, &max_profit_city, visited); printf("%d ", max_profit_city); } return 0; } |