Longest Path Algo using cpp

Author: AishwaryaGund

LongestPath.cpp

@@ -0,0 +1,51 @@
+#include<bits/stdc++.h>
+#include<algorithm>
+#include<vector>
+using namespace std;
+#define ll long long
+#define fastio  ios_base::sync_with_stdio(0); cin.tie(0);
+#define MAX 100
+
+vector<ll> adj[MAX];
+map<ll, ll> dp;
+
+ll max1(ll a, ll b)
+{
+    return (a>b?a:b);
+}
+void dfs(ll v, ll pv, ll n)
+{
+    
+    dp[v]=v;
+    ll mx=0;
+    for(auto V:adj[v])
+    {
+        if(V==pv) continue;
+        dfs(V,v,n);
+        mx=max(mx,dp[V]);
+    }
+    dp[v]+=mx;
+    
+    //return dp[1];
+}
+int main()
+{
+    fastio;
+    ll N,edge;
+    cin>>N>>edge;
+    
+    
+    for(ll i=0; i<edge; i++)
+    {
+        ll x,y;
+        cin>>x>>y;
+        adj[x].push_back(y);
+        adj[y].push_back(x);
+    }
+    dfs(2,3,N);
+    cout<<dp[2]<<"\n";
+    
+    
+    return 0;
+}
+