/in/foo.cc:5:1: error: expected ',' or ';' before 'int'
 int f[maxn],v[maxn],n,P;
 ^~~
/in/foo.cc: In function 'int dp(int)':
/in/foo.cc:8:11: error: 'f' was not declared in this scope
  int &rec=f[cur];
           ^
/in/foo.cc:11:17: error: 'n' was not declared in this scope
  for(int i=1;i<=n;i++)
                 ^
/in/foo.cc:12:11: error: 'v' was not declared in this scope
    if(cur+v[i]<=P)
           ^
/in/foo.cc:12:17: error: 'P' was not declared in this scope
    if(cur+v[i]<=P)
                 ^
/in/foo.cc: In function 'int main()':
/in/foo.cc:17:16: error: 'n' was not declared in this scope
  scanf("%d%d",&n,&P);
                ^
/in/foo.cc:17:19: error: 'P' was not declared in this scope
  scanf("%d%d",&n,&P);
                   ^
/in/foo.cc:19:16: error: 'v' was not declared in this scope
    scanf("%d",&v[i]);
                ^
/in/foo.cc:21:25: error: 'f' was not declared in this scope
  if(vis[P]) printf("%d",f[0]);
                         ^