foo.cc: In function 'int main()':
foo.cc:12:29: error: 'strlen' was not declared in this scope
   12 |         for (int i = 0; i < strlen(s); i++)
      |                             ^~~~~~
foo.cc:3:1: note: 'strlen' is defined in header '<cstring>'; did you forget to '#include <cstring>'?
    2 | #include <string>
  +++ |+#include <cstring>
    3 | using namespace std;

[Hydro](https://hydro.ac)提供评测服务