Commit 66b8348

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Add Dijkstra

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	`1`	`+#include <bits/stdc++.h>`
	`2`	`+#define ll long long`
	`3`	`+#define INF 1e18`
	`4`	`+using namespace std;`
	`5`	`+`
	`6`	`+vector<vector<pair<ll,ll>>> adj;`
	`7`	`+vector<ll> dist;`
	`8`	`+set<pair<ll,ll>> active_vertices;`
	`9`	`+`
	`10`	`+void dijkstra(ll u) {`
	`11`	`+ ll v,w;`
	`12`	`+ dist[u] = 0;`
	`13`	`+ active_vertices.insert({0, u});`
	`14`	`+`
	`15`	`+ while (!active_vertices.empty()) {`
	`16`	`+ auto it = active_vertices.begin();`
	`17`	`+ u = it->second;`
	`18`	`+ active_vertices.erase(it);`
	`19`	`+ for (auto neighbour : adj[u]) {`
	`20`	`+ v = neighbour.first;`
	`21`	`+ w = neighbour.second;`
	`22`	`+ if (dist[u] + w < dist[v]) {`
	`23`	`+ it = active_vertices.find({dist[v], v});`
	`24`	`+ if (it != active_vertices.end()) {`
	`25`	`+ active_vertices.erase(it);`
	`26`	`+ }`
	`27`	`+ dist[v] = dist[u] + w;`
	`28`	`+ active_vertices.insert({dist[v], v});`
	`29`	`+ }`
	`30`	`+ }`
	`31`	`+ }`
	`32`	`+}`
	`33`	`+`
	`34`	`+int main() {`
	`35`	`+ ll i, n, m, u, v, w, src;`
	`36`	`+ cin >> n >> m;`
	`37`	`+ adj.resize(n+1);`
	`38`	`+ dist.assign(n+1, INF);`
	`39`	`+`
	`40`	`+ for (i = 0; i < m; i++) {`
	`41`	`+ cin >> u >> v >> w;`
	`42`	`+ adj[u].push_back({v,w});`
	`43`	`+ adj[v].push_back({u,w});`
	`44`	`+ }`
	`45`	`+ cin >> src;`
	`46`	`+`
	`47`	`+ dijkstra(src);`
	`48`	`+ for (i = 1; i <= n; i++) {`
	`49`	`+ cout << i << " " << dist[i] << endl;`
	`50`	`+ }`
	`51`	`+ return 0;`
	`52`	`+}`

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