/in/foo.cc:1:26: warning: extra tokens at end of #include directive
 #include <bits/stdc++.h> using namespace std; int main() { int a=0,b=1,c; int n; cin>>n; if(n==1) cout<<setw(15)<<a; else cout<<setw(15)<<a<<setw(15)<<b; for(int i=1;i<=n-2;i++) { c=a+b; if((i-3)%4==0) cout<<endl; cout<<setw(15)<<c; a=b; b=c; } return 0; }
                          ^~~~~
/usr/lib/gcc/x86_64-linux-gnu/6/../../../x86_64-linux-gnu/Scrt1.o: In function `_start':
(.text+0x20): undefined reference to `main'
collect2: error: ld returned 1 exit status