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// 3108. Minimum Cost Walk in Weighted Graph
#include "leetcode.h"
/*
* there is an undirected weighted graph with 'n' vertices labeled from 0 to 'n
* - 1'. you are given the integer 'n' and an array 'edges', where 'edges[i] =
* [u_i, v_i, w_i]' indicates that there is an edge between vertices 'u_i' and
* 'v_i' with a weight of 'w_i'. a walk on the graph is a sequence of vertices
* and edges. the walk starts and ends with a vertex, and each edge connects the
* vertex that comes before it and the vertex that comes after it. it's
* important to note that a walk may visit the same edge or vertex more than
* once. return the array 'answer' where 'answer[i]' denotes the minimum cost of
* a walk for query 'i'.
*/
class Solution {
public:
vector<int> minimumCost(int n, vector<vector<int>> &edges,
vector<vector<int>> &query) {
vector<vector<int>> adj(n);
vector<int> cnt(n, (1 << 30) - 1);
for (vector<int> e : edges) {
int u = e[0], v = e[1], k = e[2];
adj[u].push_back(v);
adj[v].push_back(u);
cnt[u] &= k;
cnt[v] &= k;
}
queue<int> q;
vector<int> group(n, -1);
for (int i = 0; i < n; i++) {
if (group[i] == -1) {
group[i] = i;
q.push(i);
while (!q.empty()) {
int u = q.front();
q.pop();
cnt[i] &= cnt[u];
for (int v : adj[u]) {
if (group[v] == -1) {
group[v] = i;
q.push(v);
}
}
}
}
}
vector<int> ans;
for (vector<int> qs : query) {
int s = qs[0], t = qs[1];
if (s == t)
ans.push_back(0);
else
ans.push_back(group[s] == group[t] ? cnt[group[s]] : -1);
}
return ans;
}
};
int main() {
Solution obj;
vvd e1 = {{0, 1, 7}, {1, 3, 7}, {1, 2, 1}}, q1 = {{0, 3}, {3, 4}};
vvd e2 = {{0, 2, 7}, {0, 1, 15}, {1, 2, 6}, {1, 2, 1}}, q2 = {{1, 2}};
vector<int> mc1 = obj.minimumCost(5, e1, q1);
vector<int> mc2 = obj.minimumCost(3, e2, q2);
for (auto i : mc1)
printf("%d ", i); // expect: 1 -1
printf("\n");
for (auto i : mc2)
printf("%d ", i); // expect: 0
printf("\n");
}
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