Create CheapestFlightsWithinKStops.cpp

Graphs/CheapestFlightsWithinKStops.cpp

@@ -0,0 +1,42 @@
+class Solution {
+public:
+    int findCheapestPrice(int n, vector<vector<int>>& flights, int src, int dst, int K) {
+         vector<pair<int,int>>adj[n];
+        for(auto it:flights){
+            adj[it[0]].push_back({it[1],it[2]});
+
+        }
+
+        queue<pair<int,pair<int,int>>>q;
+        // {stops,{node,dist}}
+        q.push({0,{src,0}});
+        vector<int>dist(n,1e9);
+        dist[src]=0;
+
+        while(!q.empty()){
+            auto it=q.front();
+            q.pop();
+            int stops=it.first;
+            int node=it.second.first;
+            int cost=it.second.second;
+
+            if(stops>K){
+                continue;
+            }
+            for(auto iter:adj[node]){
+                int adjNode=iter.first;
+                int edgeW=iter.second;
+
+                 if(cost+edgeW<dist[adjNode] && stops<=K){
+                     dist[adjNode]=cost+edgeW;
+                     q.push({stops+1,{adjNode,cost+edgeW}});
+                 }
+            }
+
+        }
+        if(dist[dst]==1e9){
+            return-1;
+        }
+        return dist[dst];
+    }
+};