foo.cpp:1:19: warning: extra tokens at end of #include directive [enabled by default]
 #include<cstdio>  #include<cstring>  #include<cstdlib>  #include<algorithm>  #include<functional>  #include<iostream>  #include<cmath>  #include<cctype>  #include<queue>  #include<stack>  #include<map>  using namespace std;  #define INF (2139062143)  #define For(i,n) for(int i=1;i<=n;i++)  #define ForD(i,n) for(int i=n;i;i--)  #define Rep(i,n) for(int i=0;i<n;i++)  #define RepD(i,n) for(int i=n;i>=0;i--)  #define For2k(i,k,n) for(int i=k;i<=n;i++)  #define For2kD(i,k,n) for(int i=n;i>=k;i--)  #define MAXN (1000000+10)  #define MAXK (1000000000+10)  typedef long long ll;  ll n,m,x,k;  ll pow2(ll a,ll b)  {     if (b==1) return a;     if (b==0) return 1;     ll p=pow2(a,b/2)%n;     p=(p*p)%n;     if (b&1)     {         p=(p*a)%n;     }     return p;  }  int main()  {      scanf("%lld%lld%lld%lld",&n,&m,&k,&x);      ll t=pow2(10,k);      t=(t*m)%n;      t=(t+x)%n;      printf("%lld\n",t);  //  while(1);    
                   ^
foo.cpp:2:1: error: expected unqualified-id before 'return'
 return 0;  }
 ^
foo.cpp:2:12: error: expected declaration before '}' token
 return 0;  }
            ^