foo.cc:9:15: error: stray '#' in program
    9 |         i/=10;#include <iostream>
      |               ^
foo.cc: In function 'long long int ttt(int)':
foo.cc:9:16: error: 'include' was not declared in this scope
    9 |         i/=10;#include <iostream>
      |                ^~~~~~~
foo.cc:9:33: error: expected primary-expression before '>' token
    9 |         i/=10;#include <iostream>
      |                                 ^
foo.cc:11:1: error: expected primary-expression before 'using'
   11 | using namespace std;
      | ^~~~~
foo.cc:13:15: error: a function-definition is not allowed here before '{' token
   13 | int ttt(int i){
      |               ^
foo.cc:25:9: warning: empty parentheses were disambiguated as a function declaration [-Wvexing-parse]
   25 | int main()
      |         ^~
foo.cc:25:9: note: remove parentheses to default-initialize a variable
   25 | int main()
      |         ^~
      |         --
foo.cc:25:9: note: or replace parentheses with braces to value-initialize a variable
foo.cc:26:1: error: a function-definition is not allowed here before '{' token
   26 | {
      | ^

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