Language: C++

#include<bits/stdc++.h>
#define endl '\n'
#define PI 3.14159265358979323844
#define DECIMAL(n)  std::cout << std::fixed;std::cout << std::setprecision(n);
#define mp make_pair
#define pb push_back
#define mod 1000000007
#define int long long int 
#define forr(i,a,b) for (int i= a; i <b; ++i)
    using namespace std; 
 vector<int>g[100005];
 int dp[100005][2];
 int P(int source, int con , int parent){
     if(dp[source][con]!=-1)return dp[source][con];
     int ans=0; int w1=1; 
     for(auto neighbour : g[source]){
         if(neighbour!=parent ){
           w1=(w1*P(neighbour , 0 , source))%mod;
     }} int w2=1;
        if(con==0){
             for(auto neighbour : g[source]){
         if(neighbour!=parent )
             w2=(w2*P(neighbour , 1 , source))%mod;
         }
     }ans=w1;  if(con==0)ans+=w2;
     return dp[source][con]=ans%#include<bits/stdc++.h>
#define endl '\n'
#define PI 3.14159265358979323844
#define DECIMAL(n)  std::cout << std::fixed;std::cout << std::setprecision(n);
#define mp make_pair
#define pb push_back
#define mod 1000000007
#define int long long int 
#define forr(i,a,b) for (int i= a; i <b; ++i)
    using namespace std; 
 vector<int>g[100005];
 int dp[100005][2];
 int P(int source, int con , int parent){
     if(dp[source][con]!=-1)return dp[source][con];
     int ans=0; int w1=1; 
     for(auto neighbour : g[source]){
         if(neighbour!=parent ){
           w1=(w1*P(neighbour , 0 , source))%mod;
     }} int w2=1;
        if(con==0){
             for(auto neighbour : g[source]){
         if(neighbour!=parent )
             w2=(w2*P(neighbour , 1 , source))%mod;
         }
     }ans=w1;  if(con==0)ans+=w2;
     ans=ans%mod;
     return dp[source][con]=ans%mod;
 }
 signed main(){
 int n;cin>>n;
 memset(dp,-1,sizeof dp);
 forr(i,1,n){
     int a,b;cin>>a>>b;
     g[a].pb(b);
     g[b].pb(a);}
 cout<<P(1,0,1);};
 }
 signed main(){
 int n;cin>>n;
 memset(dp,-1,sizeof dp);
 forr(i,1,n){
     int a,b;cin>>a>>b;
     g[a].pb(b);
     g[b].pb(a);}
 cout<<P(1,0,1);}

Compiler output:
a.cc:26:33: error: stray '#' in program
   26 |      return dp[source][con]=ans%#include<bits/stdc++.h>
      |                                 ^
a.cc: In function 'long long int P(long long int, long long int, long long int)':
a.cc:26:34: error: 'include' was not declared in this scope
   26 |      return dp[source][con]=ans%#include<bits/stdc++.h>
      |                                  ^~~~~~~
a.cc:26:42: error: 'bits' was not declared in this scope
   26 |      return dp[source][con]=ans%#include<bits/stdc++.h>
      |                                          ^~~~
a.cc:26:47: error: 'stdc' was not declared in this scope; did you mean 'std'?
   26 |      return dp[source][con]=ans%#include<bits/stdc++.h>
      |                                               ^~~~
      |                                               std
a.cc:35:5: error: expected primary-expression before 'using'
   35 |     using namespace std;
      |     ^~~~~
a.cc:26:56: error: expected ';' before 'using'
   26 |      return dp[source][con]=ans%#include<bits/stdc++.h>
      |                                                        ^
      |                                                        ;
......
   35 |     using namespace std;
      |     ~~~~~                                               
a.cc:38:41: error: a function-definition is not allowed here before '{' token
   38 |  int P(int source, int con , int parent){
      |                                         ^
a.cc:54:13: warning: empty parentheses were disambiguated as a function declaration [-Wvexing-parse]
   54 |  signed main(){
      |             ^~
a.cc:54:13: note: remove parentheses to default-initialize a variable
   54 |  signed main(){
      |             ^~
      |             --
a.cc:54:13: note: or replace parentheses with braces to value-initialize a variable
a.cc:54:15: error: a function-definition is not allowed here before '{' token
   54 |  signed main(){
      |               ^