c++ - What is the complexity of that code? -


i looking @ code on link:
http://codeforces.com/contest/459/submission/7495216
code given directed weighted graph , wanna find longest path strictly increasing edges.
can me?

#include <iostream> #include <vector> using namespace std; const int max = 300005; vector<pair<int, int> > w[max]; int dp[max], tmp[max]; int main() {     ios::sync_with_stdio(false);     int n, m;     cin >> n >> m;     (int = 0; < m; i++)     {         int u, v, len;         cin >> u >> v >> len;         w[len].push_back(make_pair(u, v));     }     (int = 0; < max; i++)     {         (int j = 0; j < w[i].size(); j++)         {             int u = w[i][j].first, v = w[i][j].second;             tmp[v] = 0;         }         (int j = 0; j < w[i].size(); j++)         {             int u = w[i][j].first, v = w[i][j].second;             tmp[v] = max(tmp[v], dp[u] + 1);         }         (int j = 0; j < w[i].size(); j++)         {             int u = w[i][j].first, v = w[i][j].second;             dp[v] = max(dp[v], tmp[v]);         }     }     int ans = 0;     (int = 1; <= n; i++)         ans = max(ans, dp[i]);     cout << ans << endl;     return 0; }

for each node code iterates on outgoing edges. runtime complexity o(n*m) n number of nodes , m number edges.

edit: after closer @ data , code, complexity o(n+m). first , second loop iterate on edges, o(m), , third loop iterates on nodes, o(n).


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