foo.cc:1:1: error: 'include' does not name a type
    1 | include<iostream>
      | ^~~~~~~
foo.cc: In function 'int main()':
foo.cc:6:5: error: 'cin' was not declared in this scope
    6 |     cin>>n>>n1;
      |     ^~~
foo.cc:21:25: warning: statement has no effect [-Wunused-value]
   21 |                     for(i;i<=n1;i++)
      |                         ^
foo.cc:22:40: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   22 |                     if(i%400==0||i%4==0&&i%100!=0) s++;
      |                                  ~~~~~~^~~~~~~~~~
foo.cc:25:5: error: 'cout' was not declared in this scope
   25 |     cout<<s;
      |     ^~~~

[Hydro](https://hydro.ac)提供评测服务