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Commit eb34ab5

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3 files changed

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3 files changed

+238
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File renamed without changes.
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#include <bits/stdc++.h>
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using namespace std;
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typedef long int li;
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typedef long long int lli;
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typedef vector<long long int> vlli;
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typedef vector<int> vi;
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typedef stack<long long int> slli;
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typedef pair<lli, lli> plli;
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class Graph
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{
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vector<vector<plli>> adj;
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lli nodes;
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public:
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Graph(lli nodes)
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{
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this->adj.resize(nodes, vector<plli>{});
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this->nodes = nodes;
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}
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void addDirectedEdge(lli src, lli dst, lli weight)
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{
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if (src == dst)
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{
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return;
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}
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this->adj[src].emplace_back(make_pair(dst, weight));
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}
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void dijkstra()
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{
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vector<lli> distances(this->nodes, LONG_LONG_MAX);
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distances[0] = 0;
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priority_queue<plli, vector<plli>, greater<plli>> pq;
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pq.push(make_pair(0, 0));
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while (!pq.empty())
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{
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auto top = pq.top();
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pq.pop();
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lli u = top.second;
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// important for speeding up
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if (top.first > distances[u])
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{
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continue;
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}
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for (auto neighbour : this->adj[u])
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{
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lli v = neighbour.first;
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lli w = neighbour.second;
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if (distances[v] > distances[u] + w)
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{
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distances[v] = distances[u] + w;
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pq.push(make_pair(distances[v], v));
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}
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}
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}
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for (auto distance : distances)
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{
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cout << distance << ' ';
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}
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cout << '\n';
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}
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};
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void task()
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{
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lli cities, flights;
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cin >> cities >> flights;
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lli src, dst, weight;
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Graph g(cities);
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for (lli i = 0; i < flights; i++)
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{
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cin >> src >> dst >> weight;
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g.addDirectedEdge(src - 1, dst - 1, weight);
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}
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g.dijkstra();
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}
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int main()
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{
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ios::sync_with_stdio(0);
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cin.tie(0);
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task();
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return 0;
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}
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#include <bits/stdc++.h>
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using namespace std;
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typedef long int li;
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typedef long long int lli;
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typedef vector<long long int> vlli;
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typedef vector<int> vi;
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typedef stack<long long int> slli;
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typedef pair<lli, lli> plli;
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class Graph
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{
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vector<vector<lli>> adj;
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lli nodes;
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public:
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Graph(lli nodes)
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{
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this->adj.resize(nodes, vector<lli>(nodes, LONG_LONG_MAX));
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for (lli i = 0; i < nodes; i++)
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{
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this->adj[i][i] = 0;
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}
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this->nodes = nodes;
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}
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void addUndirectedEdge(lli src, lli dst, lli weight)
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{
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if (src == dst)
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{
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return;
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}
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if (this->adj[src][dst] > weight)
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{
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this->adj[src][dst] = weight;
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this->adj[dst][src] = weight;
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}
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}
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void floydWarshall()
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{
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for (lli k = 0; k < this->nodes; k++)
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{
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for (lli i = 0; i < this->nodes; i++)
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{
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for (lli j = 0; j < this->nodes; j++)
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{
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if (this->adj[i][k] == LONG_LONG_MAX || this->adj[k][j] == LONG_LONG_MAX)
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{
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continue;
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}
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if (this->adj[i][k] + this->adj[k][j] < this->adj[i][j])
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{
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this->adj[i][j] = this->adj[i][k] + this->adj[k][j];
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}
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}
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}
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}
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}
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lli shortestDistance(lli src, lli dst)
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{
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if (this->adj[src][dst] == LONG_LONG_MAX)
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{
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return -1;
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}
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return this->adj[src][dst];
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}
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};
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void task()
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{
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lli cities, roads, lenQueries;
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cin >> cities >> roads >> lenQueries;
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Graph g(cities);
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lli src, dst, weight;
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for (lli i = 0; i < roads; i++)
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{
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cin >> src >> dst >> weight;
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g.addUndirectedEdge(src - 1, dst - 1, weight);
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}
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g.floydWarshall();
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vector<lli> res;
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for (lli i = 0; i < lenQueries; i++)
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{
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cin >> src >> dst;
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res.emplace_back(g.shortestDistance(src - 1, dst - 1));
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}
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for (auto ans : res)
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{
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cout << ans << '\n';
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}
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}
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int main()
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{
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ios::sync_with_stdio(0);
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cin.tie(0);
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task();
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return 0;
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}

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