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#include <iostream> #include <vector> using namespace std; typedef long long ll; const int maxn = 300004; const ll MOD = 1e9 + 7; vector<int> graph[maxn]; ll dp[maxn][2]; void dfs(int node, int prev) { dp[node][0] = 1; // 1 with white dp[node][1] = 1; // 1 with black for(int i = 0; i < graph[node].size(); i++) { int sosed = graph[node][i]; if(sosed == prev) continue; dfs(sosed, node); dp[node][0] *= (dp[sosed][0] + dp[sosed][1]) % MOD; dp[node][1] *= dp[sosed][0] % MOD; dp[node][0] %= MOD; dp[node][1] %= MOD; } } int main() { ios_base::sync_with_stdio(false); int n; cin >> n; for(int i = 0; i < n - 1; i++) { int a, b; cin >> a >> b; a--; b--; graph[a].push_back(b); graph[b].push_back(a); } dfs(0, -1); cout << (dp[0][0] + dp[0][1]) % MOD << endl; return 0; }
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